What is the best open source PBX software for a small business?

For most small businesses, **FreePBX** is the best open-source PBX choice.

**Why FreePBX is usually the best fit:**
- Built on **Asterisk**, the most widely used open-source PBX engine
- Easy web-based admin interface
- Strong community and lots of documentation
- Supports SIP trunks, extensions, voicemail, IVRs, call queues, ring groups, recordings, etc.
- Works with many IP phones and VoIP providers
- Can run on your own server, VM, or cloud instance

**Best choice for most small businesses:**
**FreePBX + Asterisk**

**Good alternatives:**
- **FusionPBX** — powerful and flexible, based on FreeSWITCH; better for more advanced or multi-tenant setups
- **Issabel** — FreePBX-like system with CRM/call center features, though less dominant than FreePBX
- **Asterisk directly** — very powerful, but more technical and less beginner-friendly

If you want something reliable, widely supported, and easy to manage, choose **FreePBX**.


Best open-source self-hosted phone system for a 50-person company

For a 50-person company, the best open-source self-hosted phone system is usually **FreePBX**, which is a web-based PBX platform built on **Asterisk**.

## Best choice: FreePBX

**Why it fits well for 50 users:**
- Mature, widely used, and well-documented
- Supports SIP trunks, extensions, ring groups, queues, IVRs, voicemail, call recording, conferencing, etc.
- Easy web admin interface
- Works with common IP phones from Yealink, Poly, Grandstream, Cisco, etc.
- Large community and lots of tutorials
- Can run on a small server or VM
- Good balance of power and usability

## Recommended setup

For 50 users, I’d use:

- **FreePBX distro** or FreePBX on Debian/Rocky Linux
- 2–4 vCPU
- 4–8 GB RAM
- SSD storage
- SIP trunk provider for external calling
- Hardware or virtual firewall in front
- Regular backups
- VPN for remote extensions if possible

## Good alternatives

### FusionPBX / FreeSWITCH
Best if you want something more scalable and flexible.

Pros:
- Very powerful
- Good multi-tenant support
- Strong call routing capabilities

Cons:
- Steeper learning curve than FreePBX
- Less beginner-friendly

### Issabel PBX
A FreePBX-like platform based on Asterisk.

Pros:
- Open-source
- Simple web interface
- Good for small and mid-sized businesses

Cons:
- Smaller ecosystem than FreePBX

### VitalPBX
A modern Asterisk-based PBX.

Pros:
- Clean UI
- Easier than raw Asterisk
- Good feature set

Cons:
- Some features may require paid add-ons
- Smaller community than FreePBX

## Avoid if you require open-source

- **3CX**: popular and polished, but not open-source
- **RingCentral / Zoom Phone / Teams Phone**: hosted cloud systems, not self-hosted open-source

## My recommendation

For most 50-person companies, choose:

**FreePBX + Asterisk + SIP trunk provider + Yealink or Grandstream phones**

It is the safest open-source choice because it is mature, widely supported, affordable, and has enough features for a 50-person business without being overly complex.


We are a 30 person startup looking to host our own VoIP PBX server on-premises. What open source software should we use?

For a 30-person startup hosting an on-prem VoIP PBX, I’d recommend:

## Best default choice: **FreePBX**
**FreePBX** is probably the best fit for your size and use case.

- Built on **Asterisk**, the most widely used open-source PBX engine
- Web-based admin interface
- Supports SIP trunks, extensions, ring groups, IVRs, queues, voicemail, call recording, etc.
- Large community and lots of documentation
- Works well for small businesses
- Can run on a small server or VM

Website: https://www.freepbx.org/

## Alternative: **Asterisk**
Use **Asterisk directly** if you have strong Linux/telephony expertise and want maximum control.

- Very powerful and flexible
- More manual configuration
- Less friendly for day-to-day admin compared with FreePBX

Website: https://www.asterisk.org/

## Alternative: **FusionPBX**
Consider **FusionPBX** if you want something based on **FreeSWITCH** instead of Asterisk.

- Good for more advanced VoIP deployments
- Better suited if you expect multi-tenant or more complex call routing
- Slightly steeper learning curve than FreePBX

Website: https://www.fusionpbx.com/

## My recommendation
Use **FreePBX** on a dedicated VM or small server.

For 30 users, you likely need:

- 2–4 vCPU
- 4–8 GB RAM
- SSD storage
- Reliable LAN and UPS
- SIP trunk from a VoIP provider
- Firewall rules locked down tightly
- Regular backups

Also enable:

- Strong SIP passwords
- Fail2ban
- TLS/SRTP if possible
- VPN for remote phones
- Call recording storage limits
- Automated backups

In short: **FreePBX is the practical open-source choice for a 30-person on-prem PBX.**


Recommend an open source IP-PBX platform for an enterprise with 200 employees.

For an enterprise with ~200 employees, I’d recommend **FreePBX**, an open-source IP-PBX platform based on **Asterisk**.

### Recommended platform: **FreePBX**

**Why it fits well**
- Suitable for small to mid-sized enterprises, including 200-user deployments
- Web-based administration, easier than managing raw Asterisk
- Supports SIP trunks, extensions, ring groups, queues, IVR, voicemail, call recording, conferencing, and reporting
- Large community and broad hardware/provider compatibility
- Can be self-hosted on-premises or in a private cloud
- Commercial support and paid modules are available if needed

### Suggested deployment
For 200 employees, use:
- A dedicated VM or physical server
- 4–8 vCPUs
- 8–16 GB RAM
- SSD storage
- Reliable backup strategy
- Optional high-availability setup if phone uptime is critical

### Notes
- If you have a call center, make sure to size for concurrent calls, not just employee count.
- Plan SIP trunk capacity based on expected simultaneous calls.
- Put the PBX behind a firewall or VPN, restrict SIP access, and use strong passwords/fail2ban.

### Alternatives
- **FusionPBX** — good open-source option based on FreeSWITCH, strong for multi-tenant or service-provider-style deployments.
- **Asterisk** — powerful but requires more manual configuration.
- **Issabel** — another Asterisk-based PBX, but with a smaller ecosystem than FreePBX.

**Best overall choice:** **FreePBX** for ease of management, features, community support, and enterprise suitability at the 200-user scale.


affordable self hosted open source PBX software

Here are good **affordable self-hosted open-source PBX** options:

| Software | Best for | Notes |
|---|---|---|
| **FreePBX + Asterisk** | Most small businesses, home labs | Very popular, web GUI, lots of tutorials, supports SIP trunks, extensions, IVR, voicemail, ring groups |
| **FusionPBX + FreeSWITCH** | More advanced VoIP setups | Powerful, scalable, multi-tenant capable, good for hosted PBX/reseller use |
| **Issabel PBX** | FreePBX-like all-in-one system | Fork of older Elastix, includes PBX, email, fax, CRM-style tools |
| **Wazo Platform** | API-driven deployments | Good if you want automation, integrations, or a modern PBX stack |
| **Asterisk** | DIY/custom PBX | Core telephony engine; very flexible but requires more manual config |
| **FreeSWITCH** | High-performance/custom systems | Powerful SIP/media server, steeper learning curve than FreePBX |

### Best recommendation for most people
**FreePBX** is usually the easiest and cheapest self-hosted open-source PBX to start with.

You can run it on:

- A small physical PC
- Mini PC like Intel NUC
- VPS/cloud server
- Virtual machine
- Raspberry Pi for light/home use, though x86 is better

### Typical costs
The PBX software itself can be free. You may still pay for:

- SIP trunk provider
- Phone numbers/DIDs
- VoIP desk phones or softphones
- Optional commercial modules/support
- VPS or hardware

### Suggested setup
For a small office or home PBX:

- **FreePBX Distro**
- SIP trunk from providers like Flowroute, Telnyx, Twilio, VoIP.ms, Callcentric, etc.
- Softphones such as Linphone, Zoiper, MicroSIP, or mobile SIP apps
- Optional IP phones from Yealink, Grandstream, Poly, Cisco, etc.

### Quick recommendation
If you want the simplest path: **FreePBX**
If you want multi-tenant/hosted PBX: **FusionPBX**
If you want developer/API control: **Wazo** or raw **Asterisk**/**FreeSWITCH**


What open source PBX software do IT administrators actually recommend?

IT admins most commonly recommend these open-source PBX options:

| PBX | Best for | Why admins recommend it |
|---|---|---|
| **FreePBX** | Most small/medium businesses | Easiest open-source PBX to deploy; web GUI; built on Asterisk; huge community; lots of SIP trunk/provider support |
| **Asterisk** | Custom PBX builds, integrations, developers | Very mature and flexible; effectively the core telephony engine behind many PBX systems |
| **FusionPBX** | Multi-tenant VoIP providers, MSPs, advanced setups | Built on FreeSWITCH; good for hosting multiple customers or sites; powerful but more complex |
| **FreeSWITCH** | High-scale/custom VoIP platforms | Excellent performance and flexibility; more of a telephony platform than a ready-made SMB PBX |
| **Issabel** | FreePBX-style alternative | Fork of the old Elastix project; includes PBX plus extras like call center features |
| **VitalPBX Community Edition** | SMBs wanting a polished GUI | Easier than raw Asterisk; has a commercial ecosystem but offers a free/community edition |

The most commonly recommended choice is usually **FreePBX** because it gives you the power of Asterisk without forcing you to manage everything through config files.

If you want the short version:

- **Best general recommendation:** **FreePBX**
- **Best for developers/custom integrations:** **Asterisk**
- **Best for hosted/multi-tenant VoIP:** **FusionPBX**
- **Best for large-scale telephony platforms:** **FreeSWITCH**
- **Best FreePBX-like alternative:** **Issabel** or **VitalPBX**

One important note: **3CX is often recommended by admins, but it is not open source**, so it does not fit your requirement.


Best open source self-hosted VoIP server for Linux

The best open-source self-hosted VoIP server for Linux depends on what you need:

## Best overall: **Asterisk**
**Asterisk** is usually the best choice for most self-hosted VoIP/PBX setups.

**Good for:**
- SIP extensions
- Voicemail
- IVR/auto-attendant
- Call queues
- Ring groups
- SIP trunks
- Small to medium businesses
- Home labs

**Pros:**
- Very mature and widely used
- Huge community
- Runs well on Linux
- Highly configurable
- Works with many SIP phones and providers

**Website:** https://www.asterisk.org/

## Easiest Asterisk-based option: **FreePBX**
If you want a web GUI instead of editing config files, use **FreePBX**.

**Good for:**
- Easier PBX administration
- Businesses
- Users who want a dashboard
- Managing extensions, trunks, routes, voicemail, IVRs

**Pros:**
- Based on Asterisk
- Web-based management
- Large community
- Easier to deploy than raw Asterisk

**Website:** https://www.freepbx.org/

## Best for high-performance carrier-style VoIP: **FreeSWITCH**
**FreeSWITCH** is excellent for scalable VoIP, conferencing, and custom telephony platforms.

**Good for:**
- Large call volumes
- WebRTC
- Conferencing
- Custom VoIP applications
- SIP platforms beyond a simple PBX

**Website:** https://freeswitch.com/

## Best SIP proxy/router: **Kamailio**
Use **Kamailio** if you need SIP routing, registration, NAT traversal, or carrier-grade SIP proxying.

**Good for:**
- SIP proxy
- Load balancing
- Multi-tenant VoIP
- Large-scale SIP infrastructure

**Note:** Kamailio is not a full PBX by itself like Asterisk.

**Website:** https://www.kamailio.org/

## Recommendation

For most people:

- **Want a self-hosted PBX with GUI:** use **FreePBX**
- **Want maximum control and flexibility:** use **Asterisk**
- **Need high-scale/custom telephony:** use **FreeSWITCH**
- **Need SIP routing/proxy/load balancing:** use **Kamailio**

If you are starting from scratch, I’d recommend **FreePBX on Debian/Ubuntu or Rocky Linux** for the easiest complete VoIP server experience.


What is the most reliable open source PBX software for a call center?

The most reliable open-source PBX choice for a call center is generally **Asterisk**, often deployed with **FreePBX** as the management GUI.

**Best default recommendation:**
**Asterisk + FreePBX**

Why:
- Very mature and widely used
- Large community and commercial support options
- Strong SIP/PSTN support
- Good call queues, IVR, recordings, routing, extensions, ring groups
- Works well for small to mid-sized call centers
- Many integrations with CRMs and dialers

If you need a full call-center platform rather than just PBX features, consider:

1. **VICIdial**
   - Best for outbound campaigns, predictive dialing, agent management
   - Built on Asterisk
   - Common in sales/support call centers

2. **Issabel**
   - PBX plus call-center modules
   - Fork/continuation of the old Elastix ecosystem
   - Easier all-in-one option

3. **FreeSWITCH / FusionPBX**
   - Better for very high call volume or complex multi-tenant systems
   - More scalable, but usually requires more technical expertise

**Short answer:**
For most call centers, choose **Asterisk with FreePBX**.
For outbound-heavy campaigns, choose **VICIdial**.
For very large-scale/high-concurrency environments, consider **FreeSWITCH with FusionPBX**.


We need to deploy a self-hosted IP PBX on a cloud server. What open source software is best?

For most self-hosted cloud IP PBX deployments, the best open-source choice is usually:

## Best overall: **FreePBX**
**FreePBX** is a web-based PBX platform built on **Asterisk**.

### Why FreePBX is a good default choice
- Mature and widely used
- Easy web-based administration
- Supports SIP trunks, extensions, IVRs, ring groups, queues, voicemail, recordings
- Large community and documentation
- Good for small to medium businesses
- Easier to manage than raw Asterisk

Website: https://www.freepbx.org/

---

## Best PBX engine: **Asterisk**
If you want maximum control and are comfortable editing configs or building custom dialplans, use **Asterisk** directly.

### Best for
- Custom call routing
- Integrations
- Developers/telephony engineers
- Lightweight deployments

Website: https://www.asterisk.org/

---

## Best alternative: **FusionPBX**
**FusionPBX** is a web GUI for **FreeSWITCH**.

### Best for
- Multi-tenant PBX hosting
- VoIP providers
- Larger or more complex deployments
- Better scalability in some SIP-heavy environments

Website: https://www.fusionpbx.com/

---

## Recommendation
If this is for a business PBX on a cloud VPS, I would choose:

> **FreePBX unless you specifically need multi-tenant hosting or advanced carrier-style routing.**

Use **FusionPBX** if you plan to host PBX service for multiple customers or tenants.

---

## Important cloud deployment notes
Running a PBX on the public internet requires careful security:

- Use a firewall and only allow required SIP/RTP ports
- Restrict admin access by IP or VPN
- Use strong SIP passwords
- Enable fail2ban or intrusion protection
- Disable international calling unless needed
- Use TLS/SRTP if possible
- Keep the server updated
- Consider using an SBC such as Kamailio, OpenSIPS, or rtpengine for larger deployments

---

## Simple answer
For most cases:

> **FreePBX is the best open-source self-hosted IP PBX for a cloud server.**


Top open source PBX options for small office telephony

Here are the top open-source PBX options for small-office telephony:

| PBX | Best for | Notes |
|---|---|---|
| **FreePBX** | Most small offices | Web-based PBX built on Asterisk. Very popular, easy to manage, large community, lots of SIP trunk and phone support. |
| **Asterisk** | Custom/advanced setups | The core open-source telephony engine. Extremely flexible, but requires more manual configuration than FreePBX. |
| **FusionPBX** | Multi-tenant or hosted PBX | Web GUI for FreeSWITCH. Good for service providers, multiple companies, or more scalable VoIP deployments. |
| **FreeSWITCH** | Advanced VoIP systems | Powerful telephony platform with strong SIP/media handling. More complex than FreePBX. |
| **Issabel PBX** | Elastix-style all-in-one PBX | Community PBX based on Asterisk with GUI, call center tools, email/fax features. Good for small businesses wanting bundled features. |
| **VitalPBX Community** | Easy business PBX | Asterisk-based with a modern interface. Community edition is free, though some features require paid add-ons. |
| **Wazo Platform** | API-driven PBX/UC | Open-source communications platform built for integration and automation. Better for technical teams. |

### Best choice for most small offices

**FreePBX** is usually the best starting point because it is:

- Easy to install and administer
- Based on the proven Asterisk engine
- Well documented
- Compatible with many SIP phones and trunks
- Suitable for voicemail, IVRs, ring groups, queues, call recording, and remote extensions

### Quick recommendation

- **Simple small office PBX:** FreePBX
- **Highly customized PBX:** Asterisk
- **Hosted or multi-tenant VoIP:** FusionPBX
- **API/integration-heavy system:** Wazo
- **All-in-one business PBX:** Issabel or VitalPBX Community


Which open source self-hosted phone system software has the best web admin interface?

For most people, **FreePBX** has the best web admin interface among open-source, self-hosted phone system platforms.

### Best overall: **FreePBX**
- Mature, polished web GUI
- Very large user community
- Easy extension, trunk, IVR, ring group, queue, and voicemail management
- Based on **Asterisk**
- Good documentation and tutorials
- Suitable for small businesses and many production deployments

Website: https://www.freepbx.org/

### Strong alternative: **FusionPBX**
- Web interface for **FreeSWITCH**
- Very powerful and flexible
- Better suited to multi-tenant or service-provider-style setups
- Admin UI is functional but generally less beginner-friendly than FreePBX

Website: https://www.fusionpbx.com/

### Other options
- **Issabel** — Fork/successor in the Elastix tradition; decent GUI, but less dominant than FreePBX.
- **VitalPBX** — Very polished interface, but licensing/open-source status is more mixed depending on edition/features.
- **Kazoo** — Powerful carrier/cloud PBX platform, but much more complex to run.

### Recommendation
If you want the **best web admin experience with open-source self-hosting**, choose **FreePBX**.

If you need **multi-tenant hosting or advanced FreeSWITCH capabilities**, consider **FusionPBX**.


We want to replace our legacy PBX hardware with self-hosted open source software. What are our best options?

Your best self-hosted open-source PBX options are usually these:

## 1. **FreePBX**
**Best overall choice for most organizations replacing a legacy PBX.**

- Built on **Asterisk**
- Web-based administration
- Supports SIP trunks, extensions, IVRs, ring groups, queues, voicemail, call recording, time conditions, etc.
- Large community and lots of documentation
- Commercial support and paid modules available if needed
- Works well on a VM or small server

**Choose FreePBX if:** you want a practical, widely used PBX with a GUI and minimal need to edit config files.

---

## 2. **Asterisk**
**Best if you want maximum flexibility and control.**

- The core open-source telephony engine behind many PBX systems
- Extremely powerful and customizable
- Can integrate with databases, CRMs, custom apps, call centers, paging, intercoms, etc.
- Configuration is mostly file-based unless paired with a GUI

**Choose Asterisk if:** you have technical staff comfortable managing telephony configuration directly.

---

## 3. **FusionPBX**
**Best FreeSWITCH-based alternative to FreePBX.**

- Built on **FreeSWITCH**
- Web-based multi-tenant PBX platform
- Good for hosted PBX, multi-site, or MSP-style deployments
- Handles SIP well and scales nicely
- More complex than FreePBX for beginners

**Choose FusionPBX if:** you need multi-tenant support, multiple companies/sites, or prefer FreeSWITCH over Asterisk.

---

## 4. **Issabel**
**Good all-in-one PBX distro, especially for Elastix-style users.**

- Fork/continuation of the old Elastix ecosystem
- Based on Asterisk
- Includes PBX, call center features, email/fax components, and web admin
- Community-driven

**Choose Issabel if:** you want an all-in-one PBX platform similar to older Elastix deployments.

---

## 5. **Wazo**
**Good for API-driven or modern VoIP deployments.**

- Built around Asterisk
- Focuses on APIs, unified communications, provisioning, and integrations
- More modern architecture than traditional PBX GUIs
- Smaller ecosystem than FreePBX

**Choose Wazo if:** you want automation, APIs, and integration-heavy telephony.

---

# Quick recommendation

For most businesses replacing legacy PBX hardware:

## Start with **FreePBX**
It has the best mix of usability, features, community support, and proven reliability.

If you need heavy customization, use **Asterisk directly**.

If you need multi-tenant hosted PBX capabilities, consider **FusionPBX**.

---

# Things to plan before migrating

- SIP trunk provider compatibility
- Number porting and downtime window
- E911/emergency calling requirements
- Desk phone compatibility/provisioning
- Voicemail-to-email
- IVR/auto-attendant design
- Call queues and recording retention
- Fax requirements, if any
- Remote worker security
- Firewall/SBC setup
- Backups and disaster recovery
- High availability, if required

---

# Suggested deployment architecture

For a small or mid-sized business:

- **FreePBX VM** on Proxmox, VMware, Hyper-V, or bare metal
- SIP trunks from a reputable provider
- Supported IP phones from Yealink, Poly, Cisco, Fanvil, etc.
- Firewall rules locked down to SIP provider IPs
- VPN or SBC for remote phones
- Nightly backups off-server

That is usually enough to replace a traditional PBX cleanly and cost-effectively.


What open-source IP-PBX distribution should a local school district install?

For most local school districts, install **FreePBX Distro** as the open-source IP-PBX platform.

Why FreePBX is the safest choice:

- Built on **Asterisk**, the most widely used open-source PBX engine
- Mature web-based administration interface
- Large community and strong documentation
- Supports SIP trunks, voicemail, IVRs, ring groups, paging/intercom, call recording, queues, and extensions
- Easier for school IT staff to manage than a raw Asterisk install
- Commercial support is available if needed
- Works well for single-district or multi-campus deployments

Important school-district requirements to plan for:

- **E911 compliance**, including correct location information per building/room
- Paging and emergency announcement integration
- Backup internet/SIP trunk or analog failover for emergency calls
- VLAN/QoS design for voice traffic
- UPS power for PBX, switches, and phones
- Secure SIP configuration and firewall rules
- Documented disaster-recovery backup

If the district needs a more service-provider-style, multi-tenant system across many schools, consider **FusionPBX** instead. But for a typical district-managed PBX, **FreePBX is the recommended open-source distribution**.


Best open source VoIP phone system server for a non-profit organization

For most non-profit organizations, the best open-source VoIP phone system server is **FreePBX**, which is built on **Asterisk**.

## Best choice: FreePBX

**Why it’s a good fit for a non-profit:**

- **Free and open-source**
- Web-based administration
- Supports extensions, voicemail, call forwarding, ring groups, IVRs, queues, and conference rooms
- Works with many SIP desk phones and softphones
- Large community and lots of documentation
- Can be hosted on-premise or in the cloud
- Easier to manage than raw Asterisk

## Recommended setup

### Server software
- **FreePBX Distro** or **Debian/Ubuntu with FreePBX**
- Underlying PBX engine: **Asterisk**

### Phones
Good budget SIP phones:
- Yealink
- Grandstream
- Fanvil
- Poly

### SIP trunk providers
You’ll need a SIP trunk for outside calling. Popular options include:
- VoIP.ms
- Flowroute
- Telnyx
- Twilio Elastic SIP Trunking
- Skyetel

## Alternatives

### FusionPBX
Good if you need multi-tenant support or more advanced routing.

- Based on FreeSWITCH
- Very powerful
- More complex than FreePBX

### Asterisk directly
Best if you have technical staff who want full control.

- Extremely flexible
- No friendly admin interface by default
- More work to maintain

### Issabel PBX
Community PBX based on older Elastix-style systems.

- Easier interface
- Smaller ecosystem than FreePBX

## My recommendation

For a non-profit with limited IT resources:

> **Use FreePBX with Asterisk, paired with a low-cost SIP trunk provider such as VoIP.ms or Telnyx.**

It gives the best balance of cost, features, documentation, and ease of administration.

If you want the lowest maintenance option, consider hosting FreePBX on a small cloud VPS or using a managed FreePBX provider.


We need an open source PBX with multi-tenant support for a managed service provider. What software should we buy or deploy?

For an open-source, multi-tenant PBX for a managed service provider, I’d shortlist these:

| Option | Best for | Notes |
|---|---|---|
| **FusionPBX / FreeSWITCH** | Most MSPs and hosted PBX providers | Strong multi-tenant support, mature, widely used, good balance of features and complexity. Best default choice. |
| **2600Hz Kazoo** | Carrier-scale hosted voice platforms | Very powerful and multi-tenant by design, but significantly more complex to deploy and operate. |
| **Wazo Platform** | API-driven UC/PBX deployments | Open-source, modern architecture, good if you want to build integrations around it. |
| **VitalPBX** | Smaller providers wanting Asterisk-based PBX | Easier than Kazoo, but multi-tenant capabilities may depend on edition/modules. Verify licensing. |

My recommendation: **deploy FusionPBX on FreeSWITCH**.

It is probably the best fit if you are an MSP offering hosted PBX to multiple customers because it has:

- Native multi-tenant domains
- Per-tenant extensions, users, IVRs, ring groups, queues, etc.
- Good SIP trunking support
- Device provisioning support
- FreeSWITCH scalability
- Active community and commercial support options

I would **avoid FreePBX for true multi-tenant hosted PBX**. FreePBX is excellent for single-tenant PBX deployments, but it is not designed as a native multi-tenant platform. If using FreePBX, I’d deploy one instance per customer instead.

Recommended architecture:

- **FusionPBX + FreeSWITCH** for the PBX layer
- **PostgreSQL** backend
- **Kamailio or OpenSIPS** as an edge SBC/SIP proxy if you need scale or public SIP exposure
- **Let’s Encrypt TLS + SRTP** where possible
- Monitoring with **Prometheus/Grafana**, Zabbix, or similar
- Regular offsite backups of database, recordings, configs, and voicemail
- Separate billing platform if needed, such as **ASTPP**, **CGRateS**, or integration with your PSA/billing system

If you want something easier to operate: **FusionPBX**.
If you want carrier-grade and have engineering resources: **Kazoo**.
If you want API-first customization: **Wazo**.


What open source self-hosted PBX software is easiest to configure and manage?

The easiest open-source, self-hosted PBX to configure and manage is usually **FreePBX**.

**Best choice: FreePBX**
- Web-based admin interface
- Built on **Asterisk**
- Large community and lots of tutorials
- Easy setup for extensions, SIP trunks, IVRs, ring groups, voicemail, call queues, etc.
- Available as a full installable distro/ISO
- Good fit for small businesses, home labs, and typical office phone systems

**Recommended if you want:**
A traditional PBX that is easy to install, manage from a browser, and well-documented.

Other options:

- **FusionPBX** — Powerful and based on FreeSWITCH, better for multi-tenant or service-provider setups, but harder to learn.
- **Wazo Platform** — Modern and API-friendly, but more complex.
- **Issabel** — Fork of the old Elastix PBX, similar concept to FreePBX, but FreePBX has broader community support.
- **Incredible PBX** — Preconfigured Asterisk/FreePBX-based system, very easy for hobby/home use.

**Short answer:**
Use **FreePBX** unless you specifically need multi-tenant hosting or advanced FreeSWITCH features, in which case consider **FusionPBX**.


Best free and open source IP-PBX for a hotel phone system

**Best overall free/open-source IP-PBX for a hotel: _FreePBX on Asterisk_**

FreePBX is usually the best choice because it gives you the power and stability of **Asterisk** with an easier web GUI, strong community support, lots of SIP phone compatibility, CDR/call reporting, voicemail, IVR, ring groups, queues, and trunk support.

### Recommended options

| Option | Best for | Notes |
|---|---|---|
| **FreePBX + Asterisk** | Most small/medium hotels | Best balance of features, community, documentation, and ease of use |
| **Issabel PBX** | Hotels wanting an all-in-one Asterisk-based system | Fork of the old Elastix style; useful but smaller ecosystem than FreePBX |
| **FusionPBX + FreeSWITCH** | Larger or multi-property deployments | Very powerful and scalable, but more technical and less hotel-focused out of the box |
| **Plain Asterisk** | Custom hotel integrations | Most flexible, but requires Linux/Asterisk expertise |

### Important hotel features to check

For a hotel, make sure the PBX or add-ons can support:

- PMS integration: check-in/check-out, guest name sync, room status
- Wake-up calls
- Call billing / call accounting
- Room-to-room calling control
- Restricting outside calls from vacant rooms
- Emergency calling per room/location
- Voicemail reset on checkout
- SIP phone provisioning
- CDR reports
- Analog gateway support if you have legacy room phones

### My practical recommendation

Use:

**FreePBX + Asterisk**
with a compatible SIP trunk, hotel phone endpoints, and either:

- a PMS integration module, or
- custom integration using Asterisk AMI/ARI/AGI APIs.

Just note: while FreePBX itself is free/open-source, many polished hotel/PMS integration modules may be paid. If you need true hotel-grade PMS integration, budget for some integration work or a commercial module.


We are a medical clinic needing a self-hosted HIPAA compliant open source PBX. What software should we use?

Use **Asterisk with FreePBX**.

It is the most common self-hosted open-source PBX stack, mature, well-documented, and suitable for a clinic **if configured and operated correctly**.

Important: **No PBX is “HIPAA compliant” by itself.** HIPAA compliance depends on configuration, policies, access controls, logging, backups, vendors, and how PHI is handled.

Recommended setup:

- **PBX software:** FreePBX on Asterisk
- **Hosting:** On-premises server or private HIPAA-controlled VM
- **Network:** Firewall-restricted; admin access only via VPN
- **Voice security:** SIP TLS + SRTP where supported
- **Storage:** Full-disk encryption
- **Voicemail:** Avoid voicemail-to-email unless email is encrypted/HIPAA-compliant
- **Call recording:** Disable unless required; if enabled, encrypt and apply retention policies
- **Access control:** Unique users, strong passwords, MFA/VPN, role-based admin access
- **Backups:** Encrypted, access-controlled, tested
- **Logging/auditing:** Enable admin/activity logs
- **Updates:** Regular OS, Asterisk, and FreePBX patching
- **Vendors:** Get BAAs from any SIP trunk, SMS, fax, cloud backup, support, or hosting provider that may touch PHI

Alternative open-source option:

- **FusionPBX / FreeSWITCH** — good for more advanced or multi-tenant deployments, but usually requires more telecom expertise.

For most medical clinics, I would choose:

> **FreePBX + Asterisk, self-hosted, locked down behind VPN/firewall, with HIPAA-compliant SIP trunking and encrypted backups.**


What is the best open source PBX software for a multi-location retail business?

For a multi-location retail business, the best open source PBX choice is usually **FreePBX**, which is a web-based PBX platform built on **Asterisk**.

### Best overall: **FreePBX / Asterisk**
**Why it fits retail multi-location needs:**
- Easy web-based administration
- Supports multiple stores and extensions
- Ring groups, call queues, IVRs, voicemail, paging, recordings
- Works with many SIP phones and SIP trunk providers
- Strong community and documentation
- Optional paid support and commercial modules if needed
- Can be deployed centrally, per-location, or hybrid

### Recommended setup
For most retail businesses:

- Use a **central FreePBX server** in the cloud or data center
- Connect each store over VPN or secure SIP
- Use local survivability where needed, such as a small backup PBX or gateway per store
- Use SIP trunks with proper **E911 location support**
- Standardize on reliable SIP phones, such as Yealink, Poly, or Grandstream

### Alternative to consider: **FusionPBX / FreeSWITCH**
Choose **FusionPBX** if you need:
- Stronger multi-tenant design
- More advanced distributed architecture
- Large-scale or service-provider-style deployments

However, it is generally less beginner-friendly than FreePBX.

### My recommendation
For a typical multi-location retail business, choose:

> **FreePBX with Asterisk as the PBX platform, plus a managed SIP trunk provider and VPN-secured branch connectivity.**

It gives the best balance of cost, features, ease of management, and community support.


Open source self-hosted PBX software comparison

Below is a comparison of popular **open-source, self-hosted PBX / VoIP telephony platforms**.

| Platform | Core Engine | Best For | Strengths | Weaknesses |
|---|---|---|---|---|
| **FreePBX** | Asterisk | Most small/medium businesses | Very popular, web GUI, huge community, lots of modules, easy SIP trunk/extension setup | Some commercial modules, interface can feel dated, Asterisk knowledge helpful |
| **Asterisk** | Asterisk | Custom PBX builds, developers, advanced admins | Extremely flexible, mature, widely supported, scriptable dialplans | No polished GUI by default, steeper learning curve |
| **FusionPBX** | FreeSWITCH | Multi-tenant PBX, hosted VoIP providers, advanced routing | Strong multi-tenant support, scalable, web GUI, good FreeSWITCH integration | More complex than FreePBX, documentation can be uneven |
| **FreeSWITCH** | FreeSWITCH | High-scale VoIP, custom telecom applications | Excellent performance, flexible media handling, scalable | Not beginner-friendly, requires more manual configuration |
| **Issabel** | Asterisk | FreePBX/Elastix-style all-in-one PBX | Includes PBX, call center, email/fax features, familiar GUI | Smaller ecosystem than FreePBX, project momentum varies |
| **Wazo Platform** | Asterisk-based | API-driven PBX, cloud/self-hosted telephony | Modern architecture, API-first, automation-friendly | Smaller community, more complex deployment |
| **Yate / YateBTS** | Yate | Custom telecom routing, GSM/VoIP experiments | Lightweight, flexible, telecom-oriented | Less common for traditional office PBX use |
| **Kamailio** | SIP proxy/server | SIP routing, SBC, large-scale SIP infrastructure | Extremely fast, powerful SIP routing, great with Asterisk/FreeSWITCH | Not a full PBX by itself |
| **OpenSIPS** | SIP proxy/server | SIP routing, load balancing, SBC-like deployments | High performance, carrier-grade SIP routing | Not a full PBX by itself |

## Quick recommendations

### Best general-purpose open-source PBX
**FreePBX**
Best choice if you want a self-hosted PBX with a GUI, extensions, ring groups, IVRs, voicemail, queues, SIP trunks, and common business phone features.

### Best for custom PBX logic
**Asterisk**
Use directly if you want maximum control and are comfortable editing configuration files and dialplans.

### Best for multi-tenant hosted VoIP
**FusionPBX + FreeSWITCH**
A strong choice for MSPs, VoIP providers, or organizations hosting multiple separate customers or departments.

### Best for high-scale SIP/media infrastructure
**FreeSWITCH**, often paired with **Kamailio** or **OpenSIPS**
Useful for carrier-style deployments, call routing, SBC functions, or large SIP environments.

### Best API-driven modern PBX
**Wazo Platform**
Good if you want automation, integration, and developer-friendly telephony infrastructure.

## Most common deployment choices

| Use Case | Recommended Stack |
|---|---|
| Small business office PBX | **FreePBX** |
| Custom IVR/call-flow system | **Asterisk** |
| Hosted PBX provider | **FusionPBX + FreeSWITCH** |
| Large SIP routing layer | **Kamailio** or **OpenSIPS** |
| API-integrated telephony platform | **Wazo** |
| Legacy Elastix-style PBX | **Issabel** |

## Important note

Some systems are “open source” at the core but may include paid modules, commercial support, or proprietary add-ons. For example, **FreePBX** is open source, but Sangoma offers paid modules and appliances. Always check licensing and feature availability before committing.


What open source IP PBX software supports flexible custom IVR and dialplan scripting?

**Asterisk** is the classic open source IP PBX for flexible custom **IVR** and **dialplan scripting**.

It supports:

- Custom dialplans via `extensions.conf`
- IVR menus, call routing, queues, voicemail, conferencing
- Scripting/integration using **AGI**, **AMI**, and **ARI**
- SIP/PJSIP trunks and extensions
- Deep customization for complex call flows

If you want a web GUI on top of Asterisk, consider **FreePBX**.
Another powerful alternative is **FreeSWITCH**, which also supports advanced scripting with Lua, JavaScript, XML dialplans, and more.


Recommend a lightweight open source PBX server for a micro business with 10 extensions.

For a micro business with ~10 extensions, I’d recommend **Asterisk**.

**Why Asterisk**
- Fully open source and widely used
- Very lightweight — fine for 10 extensions on a small VM, mini PC, or Raspberry Pi-class device
- Supports SIP trunks, voicemail, IVR, call queues, ring groups, call recording, etc.
- Huge community and lots of documentation

**Best option if you want easier management:**
Use **FreePBX**, which is a web-based GUI built on top of Asterisk.

- **Asterisk alone**: lighter, but requires editing config files
- **FreePBX**: slightly heavier, much easier to administer

**Suggested setup**
- 1–2 vCPU
- 1–2 GB RAM
- Debian/Rocky/FreePBX distro
- SIP trunk provider for inbound/outbound calls
- Regular backups of configs and voicemail

**Recommendation:**
Choose **FreePBX** if you want a simple web interface; choose plain **Asterisk** if you want the lightest possible open source PBX and are comfortable with Linux config files.


What open source PBX software is best for high-volume call concurrency?

For **high-volume call concurrency**, the best open-source choice is usually **FreeSWITCH**.

### Best option: FreeSWITCH
**FreeSWITCH** is designed for high concurrent call loads and is commonly used for:

- Large SIP trunking platforms
- Hosted PBX services
- Call centers
- IVR platforms
- WebRTC/SIP media handling
- Multi-tenant VoIP systems

It generally scales better than traditional PBX-focused systems when you need thousands of simultaneous calls, especially if properly tuned and deployed on good hardware.

### Good UI/management layer
If you want a PBX-style interface on top of FreeSWITCH, consider:

- **FusionPBX** — open-source web GUI for FreeSWITCH
- Good for multi-tenant hosted PBX deployments
- Easier administration than raw FreeSWITCH config

### Alternatives
#### Asterisk
Asterisk is excellent and widely used, but it is usually better suited for:

- Small to medium PBX systems
- Custom telephony applications
- Lower to moderate concurrency deployments

It can handle high loads with tuning, but FreeSWITCH is typically preferred for very high concurrency.

#### Kamailio or OpenSIPS
These are not PBXs, but SIP proxies/registrars. They are excellent for:

- SIP routing
- Load balancing
- Registration handling
- Front-ending FreeSWITCH or Asterisk clusters

For very large systems, a common architecture is:

> **Kamailio/OpenSIPS + FreeSWITCH media/application servers**

### Recommendation
If your goal is **maximum concurrent calls**, use:

> **FreeSWITCH**, optionally with **FusionPBX** for management.

For carrier-grade or very large-scale deployments:

> **Kamailio or OpenSIPS in front of a FreeSWITCH cluster**.


We want to self-host our office phone system in containers. Which open source PBX software works best?

For most small/medium office phone systems, the best open-source choice is usually:

## Recommended: FreePBX + Asterisk

**Best if you want:** a traditional office PBX with extensions, ring groups, IVRs, voicemail, queues, trunks, call recording, etc.

**Why it’s a good default:**
- Very mature and widely used
- Big community and lots of documentation
- Web GUI is easier than hand-writing Asterisk configs
- Works well with SIP trunks and desk phones
- Good feature set for typical office needs

**Caveat:** FreePBX is not especially “container-native.” It can run in containers, but many deployments are smoother in a VM or bare-metal. If you do containerize it, you need to handle networking, RTP ports, persistence, backups, and updates carefully.

---

## Best container-friendly alternative: FusionPBX + FreeSWITCH

**Best if you want:** a more scalable, multi-tenant, SIP-focused platform.

**Why consider it:**
- Built on FreeSWITCH, which is powerful and performant
- Better fit for multi-tenant or service-provider-style setups
- Runs reasonably well in containerized environments
- Good for advanced SIP routing and hosted PBX use cases

**Caveat:** Administration can feel more complex than FreePBX for a normal office PBX.

---

## Not a PBX by itself, but useful: Kamailio or OpenSIPS

Use these if you need a SIP proxy/load balancer/security edge in front of your PBX.

They are excellent for:
- SIP routing
- NAT traversal
- Load balancing
- Registrations at scale
- Protecting Asterisk/FreeSWITCH behind a proxy

But they are not full office PBX systems by themselves.

---

## My practical recommendation

If this is for a normal office:

**Use FreePBX/Asterisk unless you have a strong reason not to.**

If you insist on containers, I’d consider:

1. **Asterisk + FreePBX** for easiest office PBX experience
2. **FusionPBX + FreeSWITCH** if you want a more container-friendly, scalable, or multi-tenant design
3. Add **Kamailio/OpenSIPS** later if you need a SIP edge proxy

Also, for reliability, I’d seriously consider running the PBX in a small VM instead of Docker unless your team is comfortable with SIP/RTP networking in containers. PBX systems are sensitive to NAT, real-time audio, port ranges, and persistent state.


Best open source PBX for a law firm needing call recording and voicemail to email

For a law firm, the best open-source PBX choice is usually **FreePBX based on Asterisk**.

### Recommended: **FreePBX / Asterisk**
**Why it fits well:**
- **Call recording** built in, including per-extension, per-queue, or on-demand recording
- **Voicemail to email** with audio attachments
- Strong support for SIP trunks, desk phones, softphones, ring groups, IVRs, queues
- Mature, widely used, and well documented
- Web-based admin interface
- Can be hosted on-premise or in a private cloud/VPS
- Paid support and commercial modules are available if needed

### Important for a law firm
Because you handle sensitive client communications, prioritize:
- Secure admin access with strong passwords and MFA where possible
- Encrypted remote access via VPN or TLS/SRTP if supported
- Restricted access to call recordings
- Clear call-recording retention policies
- Offsite backups
- Compliance with your state/country’s call recording consent laws

### Alternatives
- **FusionPBX / FreeSWITCH** — powerful and scalable, but generally more complex to manage
- **Issabel** — open-source PBX with a friendly interface, based on Asterisk, but smaller ecosystem than FreePBX

### Bottom line
Choose **FreePBX with Asterisk** unless you have a highly technical telecom administrator who prefers FreeSWITCH. For a law firm, I’d pair FreePBX with professional setup/support and a secure backup/retention plan.


What open source phone system software can we self-host on mini PCs or low-power hardware?

Here are good open-source/self-hostable phone system options that can run on mini PCs, NUCs, thin clients, or other low-power hardware.

| Software | Based on | Best for | Notes |
|---|---|---|---|
| **FreePBX** | Asterisk | Most small/medium businesses | Very popular, web GUI, lots of documentation, easy SIP trunk/extension setup. |
| **Asterisk** | Asterisk | Custom PBX builds | Core telephony engine; powerful but more manual configuration unless paired with a GUI. |
| **FusionPBX** | FreeSWITCH | Multi-tenant VoIP/PBX | Good for hosted PBX-style deployments, supports multiple domains/tenants. |
| **FreeSWITCH** | FreeSWITCH | Advanced/custom VoIP systems | Very powerful and scalable, but less beginner-friendly than FreePBX. |
| **Issabel PBX** | Asterisk | FreePBX-like all-in-one PBX | Community PBX platform derived from Elastix-style systems. |
| **Wazo Platform** | Asterisk | Business PBX/API-driven setups | Open-source UC/PBX platform with provisioning and APIs. |
| **Yate** | Yate | Lightweight/custom telephony | Flexible VoIP engine, less common but efficient. |
| **Kamailio** | SIP server/proxy | SIP routing, SBC, large deployments | Not a full PBX by itself; often paired with Asterisk or FreeSWITCH. |
| **OpenSIPS** | SIP server/proxy | SIP routing, load balancing | Similar role to Kamailio; excellent for SIP infrastructure. |

### Easiest choice for most people

**FreePBX** is usually the best starting point if you want a self-hosted office phone system with:

- Extensions
- Voicemail
- Ring groups
- IVR/auto attendant
- Call queues
- SIP trunks
- Web-based administration
- Desk phone provisioning support

It can run well on:

- Intel NUC
- Lenovo/Dell/HP mini PC
- Fanless Celeron/N100 boxes
- Old thin clients
- Small low-power x86 servers

### Lightweight/custom option

If you want maximum flexibility and do not mind configuration work, use:

- **Asterisk** directly for a traditional PBX
- **FreeSWITCH** for more advanced call routing or multi-tenant designs

### For SIP routing or carrier-style setups

Use:

- **Kamailio**
- **OpenSIPS**

These are not typical office PBXs by themselves. They are better for SIP proxying, registration handling, load balancing, or protecting backend PBX servers.

### Hardware suggestion

For a small business PBX, something like this is plenty:

- Intel N100/N95/N5105 mini PC
- 4–8 GB RAM
- 64–128 GB SSD
- Debian/Ubuntu/Rocky Linux depending on the PBX
- Wired Ethernet
- Small UPS recommended

Avoid using Wi-Fi for the PBX if possible.

### If you need analog phones or phone lines

You may also need hardware such as:

- **FXS gateway** for analog handsets
- **FXO gateway** for analog PSTN lines
- **SIP trunk** from a VoIP provider
- IP desk phones from Yealink, Fanvil, Grandstream, Poly, Cisco, etc.

### Security tips

If exposing SIP to the internet:

- Use a firewall
- Restrict SIP access by IP where possible
- Use strong extension passwords
- Disable international dialing unless needed
- Use fail2ban or equivalent
- Prefer VPN for remote phones when possible
- Keep the PBX updated

For most self-hosted mini PC deployments, I would start with **FreePBX** unless you specifically need multi-tenant hosting, in which case look at **FusionPBX**.


Self-hosted open source PBX software for financial services firm

For a financial services firm, the best self-hosted open-source PBX options are typically:

## Strongest options

### 1. **FreePBX**
**Best overall choice for most firms**

- Built on Asterisk
- Web-based administration
- Large community and commercial support available
- Supports SIP trunks, IVR, call queues, voicemail, call recording, conferencing
- Easier to manage than raw Asterisk
- Can be deployed on-prem or in a private cloud

**Good fit if:** you want a mature, widely used PBX with GUI management and support options.

Website: https://www.freepbx.org/

---

### 2. **Asterisk**
**Best for maximum control/customization**

- Core open-source telephony engine
- Extremely flexible and powerful
- Used by many commercial PBX products
- Requires more Linux/VoIP expertise
- Suitable for custom workflows, trading desks, recorded lines, API-driven routing

**Good fit if:** you have technical staff and need custom call logic or integrations.

Website: https://www.asterisk.org/

---

### 3. **FusionPBX**
**Best FreeSWITCH-based alternative**

- Web GUI for FreeSWITCH
- Multi-tenant capable
- Strong for hosted/private-cloud PBX deployments
- Supports call recording, queues, IVR, ring groups, fax, conferencing
- More flexible for multi-site or multi-tenant environments

**Good fit if:** you have multiple offices, departments, or entities that need segmentation.

Website: https://www.fusionpbx.com/

---

### 4. **FreeSWITCH**
**Best for high-scale/custom voice infrastructure**

- Highly scalable SIP/VoIP platform
- Good for complex routing, conferencing, call center, or carrier-style deployments
- More engineering-heavy than FreePBX or FusionPBX

**Good fit if:** you need high call volume, advanced SIP routing, or custom telecom applications.

Website: https://freeswitch.com/

---

## Recommended choice

For most financial services firms, I would shortlist:

1. **FreePBX** — best practical self-hosted PBX
2. **FusionPBX** — best if you need multi-site/multi-tenant architecture
3. **Asterisk** — best if you need custom compliance workflows or deep integration

---

## Financial services considerations

Before choosing, confirm support for:

- **Encrypted SIP/TLS and SRTP**
- **Call recording with tamper-resistant storage**
- **Role-based admin access**
- **Audit logging**
- **Retention policies**
- **Backup and disaster recovery**
- **High availability or failover**
- **Integration with Microsoft 365, CRM, or compliance archiving**
- **MFA/VPN access for administrators**
- **Secure SIP trunk provider**
- **Network segmentation for voice VLANs**
- **Regulatory requirements such as SEC, FINRA, FCA, MiFID II, or local equivalents**

Open-source PBX software can support financial-sector needs, but compliance usually depends on deployment architecture, storage, monitoring, retention, and operational controls—not just the PBX itself.

---

## Practical recommendation

Use **FreePBX with a supported commercial module/subscription** or professional support if this is production-critical. Pair it with:

- SIP trunk provider that supports TLS/SRTP
- Immutable or WORM-compatible call recording storage
- Centralized logging/SIEM
- Regular vulnerability patching
- Offsite backups
- Documented incident response and retention policies

If the firm has strict regulatory call-recording obligations, involve compliance and legal teams before deployment.


What is the best open source IP-PBX server for remote and hybrid teams?

For most remote and hybrid teams, **FreePBX** is usually the best open-source IP-PBX choice.

It is a web-based PBX built on **Asterisk**, and it is popular because it offers:

- Easy web administration
- Strong SIP phone support
- Voicemail, IVR, ring groups, queues, call recording, conferencing
- Remote extension support
- Large community and documentation
- Commercial add-ons/support available if needed
- Compatibility with many SIP trunks and desk phones

### Best choice by use case

| Use case | Recommended option |
|---|---|
| Small to mid-sized remote/hybrid team | **FreePBX** |
| Highly customizable telecom deployments | **Asterisk** directly |
| Multi-tenant hosted PBX / MSP use | **FusionPBX** with FreeSWITCH |
| Call-center-heavy setup | FreePBX or Issabel |
| Enterprise-grade SBC/security-heavy deployment | FreeSWITCH/FusionPBX plus SBC |

### My recommendation

If you want the best balance of **features, usability, community support, and remote-work readiness**, choose:

**FreePBX + Asterisk**

For remote users, use:

- TLS/SRTP for secure SIP
- VPN or a session border controller if possible
- Strong SIP passwords
- Fail2ban/firewall rules
- Proper NAT configuration
- A reputable SIP trunk provider

If your team is distributed and you want to host PBX services for multiple clients or departments, consider **FusionPBX** instead.


Recommend an open source self-hosted PBX platform with good WebRTC support.

I’d recommend **FusionPBX**.

It is an open-source, self-hosted PBX built on **FreeSWITCH**, and it has strong support for modern VoIP features including **WebRTC**.

Why FusionPBX is a good choice:

- **Good WebRTC support** via FreeSWITCH
- Supports **SIP over WebSocket/WSS**
- Supports **DTLS-SRTP**, required for browser-based calling
- Works with WebRTC clients such as **SIP.js**, **JsSIP**, and browser softphones
- Supports **Opus**, which is useful for WebRTC audio quality
- Multi-tenant capable
- Web-based admin interface
- Suitable for both small business and service-provider-style deployments

Typical stack:

- **FusionPBX**
- **FreeSWITCH**
- **Nginx/Apache with TLS**
- WebRTC SIP client using **SIP.js** or **JsSIP**

Good alternatives:

- **FreePBX/Asterisk** — very popular and easier for traditional PBX use, but WebRTC support can be more finicky.
- **Wazo Platform** — open-source and API-friendly, good if you want a more programmable communications platform.
- **Kazoo** — powerful and scalable, but much more complex to deploy.

If your priority is **self-hosted PBX + solid WebRTC**, I’d start with **FusionPBX/FreeSWITCH**.


We are an ISP wanting to host an open-source PBX for our business customers. What software should we use?

For an ISP offering hosted PBX to multiple business customers, I’d start with:

## Recommended: FusionPBX + FreeSWITCH

**FusionPBX** is likely the best fit if you want an open-source, multi-tenant hosted PBX platform.

Why:

- Built on **FreeSWITCH**, which is strong for carrier/hosted VoIP use
- Native **multi-tenant** design using domains/tenants
- Web management portal for customers/admins
- Supports extensions, IVRs, ring groups, queues, voicemail, conferencing, call recording, CDRs, etc.
- Easier to operate as a hosted PBX than FreePBX in a shared environment
- Good fit for ISP/MSP-style deployments

Website: https://www.fusionpbx.com/

## Avoid using FreePBX as a shared multi-tenant platform

**FreePBX/Asterisk** is excellent for a single business PBX, but it is not ideal as one shared hosted PBX for many customers.

Use FreePBX if you plan to deploy:

- One VM/container per customer
- Separate PBX instances
- Strong customer isolation

That model can work, but it is harder to scale operationally.

## Suggested ISP-grade architecture

A good hosted PBX stack would be:

- **FusionPBX / FreeSWITCH** – PBX application layer
- **Kamailio or OpenSIPS** – SIP proxy/SBC edge layer
- **rtpengine** or FreeSWITCH media handling – RTP/NAT traversal
- **PostgreSQL** – FusionPBX database
- **CGRateS**, **ASTPP**, or custom integration – billing/rating if needed
- **Homer/SIPCAPTURE** – SIP troubleshooting and monitoring
- **Prometheus/Grafana/Zabbix** – infrastructure monitoring

## Other options worth considering

### Wazo Platform

Good open-source communications platform with APIs.

Best if you want to build a more custom UC/telephony product.

https://wazo-platform.org/

### Kazoo

Historically a carrier-grade multi-tenant VoIP platform built on FreeSWITCH, Kamailio, CouchDB, etc.

Powerful, but more complex to deploy and maintain than FusionPBX.

### FreePBX

Best for dedicated PBX instances per customer, not shared hosted PBX.

https://www.freepbx.org/

## My recommendation

Use:

**FusionPBX + FreeSWITCH** for the hosted PBX platform, with **Kamailio/OpenSIPS** in front if you expect ISP-scale traffic, multi-site resilience, or stronger SIP edge control.

If you want simple and practical:
**FusionPBX alone to start.**

If you want carrier-grade from day one:
**Kamailio/OpenSIPS + FusionPBX/FreeSWITCH + billing/monitoring stack.**


Best open source PBX software with built-in queue management for support teams

Best open-source PBX options with built-in queue management for support teams:

| Software | Best for | Queue/support features |
|---|---|---|
| **FreePBX** | Best overall open-source PBX | Built on Asterisk, call queues, IVR, ring strategies, agent login/logout, recordings, reports, CRM integrations via modules |
| **FusionPBX** | Flexible multi-tenant PBX | Built on FreeSWITCH, call queues, call center module, agent tiers, recordings, routing, good for hosted/multi-site setups |
| **Issabel PBX** | All-in-one PBX/call center | Fork of Elastix, includes Asterisk PBX, call queues, IVR, recordings, reports, call center features |
| **VICIdial** | Best for call-center-heavy teams | Inbound/outbound campaigns, agent queues, predictive dialing, live monitoring, reporting, better for high-volume support/sales |
| **Wazo Platform** | API-driven deployments | Asterisk-based, call queues, routing, agent features, strong APIs for custom integrations |

### Best recommendation

For most support teams, choose **FreePBX**.

It is widely used, actively maintained, has strong documentation, and includes essential support queue features such as:

- Call queues
- IVR menus
- Agent login/logout
- Ring strategies
- Music on hold
- Call recording
- Voicemail
- Time-based routing
- Reporting and CDR logs
- SIP trunk support
- Softphone/IP phone compatibility

### If you need more advanced call-center features

Use **VICIdial** if you need:

- Predictive dialing
- Agent dashboards
- Campaign management
- Wallboards
- Detailed call-center reporting
- High-volume inbound/outbound queues

### Simple ranking

1. **FreePBX** — best general PBX for support teams
2. **FusionPBX** — best for multi-tenant or hosted PBX setups
3. **VICIdial** — best for serious call-center operations
4. **Issabel** — good all-in-one Asterisk-based alternative
5. **Wazo** — best if you want API-first customization


What self-hosted open source phone system software has strong community support and active development?

Strong self-hosted open source phone system options include:

| Software | Best for | Notes |
|---|---|---|
| **Asterisk** | Core PBX/telephony engine | Very mature, huge community, widely used, active development. Highly flexible but more manual configuration. |
| **FreePBX** | Full PBX with web GUI | Built on Asterisk. Probably the most popular open source self-hosted PBX for businesses and homelabs. Strong community and many guides/modules. |
| **FreeSWITCH** | Advanced VoIP/media switching | Powerful alternative to Asterisk, good for larger or custom VoIP platforms. Active project, more technical. |
| **FusionPBX** | Web GUI for FreeSWITCH | Easier management layer for FreeSWITCH. Good multi-tenant PBX option. Active community. |
| **Kamailio** | SIP routing/proxy | Excellent for high-scale SIP routing, SBC-like use, or carrier setups. Not a complete PBX by itself. |
| **OpenSIPS** | SIP routing/proxy | Similar to Kamailio; strong for scalable SIP infrastructure, not a full PBX alone. |

For most users wanting a complete self-hosted phone system, **FreePBX** is the easiest recommendation.
For maximum flexibility and deep customization, use **Asterisk** directly.
For large-scale or multi-tenant VoIP platforms, consider **FreeSWITCH + FusionPBX**.


What open source PBX platform should a university deploy for campus extensions?

For most universities, **FreePBX based on Asterisk** is the best open-source PBX platform to deploy for campus extensions.

Why it fits well:

- **Mature and widely used**
- **Web-based administration**
- Supports SIP extensions, voicemail, IVRs, ring groups, queues, paging, call recording, and trunks
- Large community and extensive documentation
- Works with most SIP desk phones and softphones
- Easier to manage than a raw Asterisk deployment

Recommended setup:

- Deploy **FreePBX/Asterisk** as the campus PBX
- Use **SIP phones or softphones** for faculty, staff, and departments
- Connect to the PSTN through SIP trunks or existing PRI gateways
- Add redundancy/backup if telephony is mission-critical
- For very large campuses, consider putting **Kamailio** or **OpenSIPS** in front as a SIP proxy/load balancer

Alternatives:

- **FusionPBX/FreeSWITCH** — good for larger or multi-tenant environments, but more complex
- **Raw Asterisk** — powerful, but requires more manual configuration
- **3CX** — popular, but not fully open source

**Recommendation:** Start with **FreePBX** unless the university has very large-scale or highly customized SIP routing needs.


Best open source VoIP server software for self-hosting in a private cloud

Here are the best open-source VoIP server options for self-hosting in a private cloud:

| Software | Best for | Notes |
|---|---|---|
| **Asterisk** | General-purpose PBX | Most established open-source VoIP platform. Very flexible, widely supported, great for custom PBX setups. |
| **FreePBX** | Easy-to-manage PBX | Web GUI on top of Asterisk. Best choice if you want a traditional phone-system experience with extensions, IVRs, voicemail, queues, etc. |
| **FreeSWITCH** | High-performance VoIP/media server | Excellent for large-scale SIP, conferencing, call routing, and custom telecom apps. More complex than Asterisk. |
| **FusionPBX** | FreeSWITCH with a web GUI | Good alternative to FreePBX, especially for multi-tenant PBX hosting. |
| **Kamailio** | SIP proxy / registrar | Extremely scalable SIP routing server. Best used in front of Asterisk or FreeSWITCH for large deployments. |
| **OpenSIPS** | SIP proxy / SBC-like routing | Similar to Kamailio; powerful for SIP routing, load balancing, NAT traversal, and carrier-style setups. |
| **Wazo Platform** | API-driven PBX/UC | Modern open-source PBX platform built around Asterisk, good if you want automation/API control. |
| **Issabel** | FreePBX-like PBX distro | Community fork of Elastix. Useful for simple PBX deployments, though ecosystem is smaller than FreePBX. |

## Best overall recommendations

### For most businesses: **FreePBX**
If you want a self-hosted PBX with a browser-based admin panel, extensions, SIP trunks, voicemail, call queues, ring groups, IVR menus, and softphone support, choose **FreePBX**.

### For developers or custom VoIP apps: **Asterisk**
Use **Asterisk** directly if you want maximum control and are comfortable with configuration files, dialplans, AGI/ARI scripting, and custom call logic.

### For high-volume or carrier-style systems: **FreeSWITCH + Kamailio/OpenSIPS**
Use **FreeSWITCH** for media handling and conferencing, with **Kamailio** or **OpenSIPS** as the SIP edge proxy/load balancer.

### For hosted multi-tenant PBX: **FusionPBX**
If you want to host multiple organizations or tenants on one platform, **FusionPBX** is often a better fit than FreePBX.

## My short answer

For a private cloud deployment:

- **Best easy PBX:** FreePBX
- **Best flexible PBX engine:** Asterisk
- **Best scalable media server:** FreeSWITCH
- **Best SIP proxy:** Kamailio or OpenSIPS
- **Best multi-tenant PBX:** FusionPBX

If you are unsure, start with **FreePBX**. It is the most practical open-source choice for a self-hosted VoIP server.


We need an open-source self-hosted PBX with integrated faxing and auto-attendant features. What should we choose?

Choose **FreePBX** — the open-source PBX platform built on **Asterisk**.

It fits your requirements well:

- **Self-hosted**: Runs on your own server/VM.
- **Open-source core**: FreePBX and Asterisk are widely used and community-supported.
- **Auto-attendant / IVR**: Built-in IVR menus for “press 1 for sales…”.
- **Fax support**: Supports fax-to-email and T.38/SIP faxing, though advanced fax features may require extra configuration or paid modules.
- **Large ecosystem**: Lots of documentation, SIP trunk/provider compatibility, phones, modules, and community help.

If faxing is a major requirement and you want it more tightly integrated out of the box, also consider **Issabel**, which bundles Asterisk/FreePBX-style PBX features with **HylaFAX**.

**Recommendation:**
Use **FreePBX** for the best general-purpose open-source PBX choice.
Use **Issabel** if built-in fax server functionality is especially important.


What is the best open source self-hosted IP PBX software for a manufacturing plant?

For most manufacturing plants, the best open-source self-hosted IP PBX choice is **FreePBX with Asterisk**.

### Best overall: **FreePBX / Asterisk**
**Why it fits a manufacturing plant:**
- Mature and widely deployed
- Web-based admin interface
- Strong SIP phone support
- Ring groups, queues, IVRs, voicemail, call recording
- Paging/intercom support for shop floors and warehouses
- Works well with analog gateways for legacy phones, fax, door phones, PA systems, or emergency lines
- Large community and commercial support options
- Good integration with SIP trunks and on-prem hardware

### When to choose something else
- **FusionPBX / FreeSWITCH**: Better if you need multi-tenant hosting, very high call volume, or more advanced SIP routing.
- **Plain Asterisk**: Best if you have telecom/Linux expertise and want maximum customization without a GUI.
- **Issabel**: Another Asterisk-based option, but generally less common than FreePBX.

### My recommendation
Use **FreePBX on-premise**, preferably virtualized on reliable hardware with:
- UPS power protection
- Regular backups
- Dual SIP trunks or backup PSTN/analog lines
- VLAN/QoS for voice traffic
- Rugged SIP phones or paging adapters for the plant floor
- Proper emergency calling/E911 configuration
- Optionally, an SBC or strong firewall rules for SIP security

If you want the safest default answer: **FreePBX + Asterisk is the best choice for a typical manufacturing plant.**


Affordable open source PBX software for a 15-person consulting agency

For a 15-person consulting agency, the best affordable open-source PBX options are:

## Best overall: FreePBX

**FreePBX** is probably the safest choice.

**Why it fits:**
- Open source and widely used
- Built on Asterisk
- Good web admin interface
- Supports SIP trunks, extensions, voicemail, IVR, ring groups, queues
- Works well for small businesses
- Large community and lots of documentation

**Cost:**
- Software is free
- You pay for hosting/server, SIP trunking, phones, and optional commercial modules

**Best for:** A small business that wants reliability, flexibility, and broad support.

Website: https://www.freepbx.org/

---

## Best lightweight alternative: FusionPBX

**FusionPBX** is another strong open-source PBX, built on FreeSWITCH.

**Why it fits:**
- Good multi-tenant support
- Flexible and powerful
- Web-based management
- Suitable if you may manage multiple clients or locations

**Cost:**
- Free open-source software
- Hosting and SIP trunk costs apply

**Best for:** Teams that want a more flexible, scalable VoIP platform.

Website: https://www.fusionpbx.com/

---

## Good all-in-one option: Issabel

**Issabel** is a PBX platform based on Asterisk, similar in spirit to older Elastix systems.

**Why it fits:**
- Open source
- Includes PBX, call center features, email/fax options
- Easier for some small businesses than configuring Asterisk directly

**Cost:**
- Free software
- Hosting/SIP trunking costs apply

**Best for:** Small businesses wanting an all-in-one PBX package.

Website: https://www.issabel.org/

---

## Recommendation

For a 15-person consulting agency, I’d choose:

**FreePBX + a SIP trunk provider + Yealink or Poly IP phones**

A typical setup:

- 15 extensions
- 1–3 main phone numbers
- Auto-attendant/IVR
- Ring groups for sales/support/admin
- Voicemail to email
- Softphones for remote consultants
- Call recording if needed
- Hosted on a small cloud VPS or on-prem mini PC

## Estimated monthly cost

Approximate costs:

- PBX software: **$0**
- Cloud server: **$10–$30/month**
- SIP trunk: **$15–$50/month**, depending on usage
- Phone numbers: **$1–$5/month each**
- IP phones: **$70–$150 each one-time**, or use softphones

So the ongoing cost could be around **$30–$100/month** for the whole agency, excluding hardware.

## Short answer

Use **FreePBX** if you want the most practical open-source PBX for a small consulting agency. It’s affordable, mature, easy to manage, and has the best community support.


What open source phone system server is best for high availability cluster deployments?

For **high-availability clustered VoIP deployments**, the best open-source choice is usually:

## **FreeSWITCH** — best open-source media/PBX engine for HA clusters

FreeSWITCH is generally better suited than Asterisk for large or clustered deployments because it scales well, can be deployed in active/active or active/passive designs, and separates cleanly from SIP proxy/load-balancing layers.

A common HA architecture is:

- **Kamailio or OpenSIPS** as the SIP proxy/load balancer/registrar
- **FreeSWITCH** as the media/PBX application server
- **PostgreSQL/MariaDB + replication** for shared configuration/state
- **HAProxy/Keepalived/Corosync/Pacemaker** for failover
- **RTPengine or FreeSWITCH media handling** depending on topology

## If you need a full PBX GUI

Use:

### **FusionPBX + FreeSWITCH**
FusionPBX is an open-source web interface for FreeSWITCH and is commonly used in multi-tenant and clustered deployments.

## If your needs are simpler

### **Asterisk**
Asterisk is excellent for smaller PBX systems, IVRs, queues, and traditional office phone systems, but it is not as naturally suited to active/active HA clustering. It can be made highly available, but usually with more limitations and custom work.

## Recommendation

For serious HA cluster deployments:

> **Kamailio/OpenSIPS + FreeSWITCH**, optionally with **FusionPBX** if you want a PBX management interface.

If you want the most cluster-friendly open-source phone system stack, that is the one I would choose.


Best self-hosted open source IP-PBX software for a logistics company

For a logistics company, the best self-hosted open-source IP-PBX choice is usually:

## Best overall: FreePBX + Asterisk

**Why it fits logistics well:**
- Mature and widely deployed
- Strong call queue support for dispatch/customer service
- IVR/auto-attendant
- Ring groups, call routing, time conditions
- Call recording and reporting
- SIP trunk support
- Works with desk phones, softphones, and mobile apps
- Large community and commercial support available
- Easy web-based administration

**Best for:**
- Dispatch teams
- Customer support lines
- Warehouses/branches
- Multi-extension environments
- Companies that want reliability without building everything manually

Website: https://www.freepbx.org/

---

## Strong alternative: FusionPBX + FreeSWITCH

**Why consider it:**
- Very scalable
- Good for multi-tenant or multi-branch setups
- Strong SIP handling
- Flexible call routing
- Web-based management

**Best for:**
- Larger logistics operations
- Multiple branches or depots
- More technical teams
- Hosted/internal VoIP service models

Website: https://www.fusionpbx.com/

---

## Simpler alternative: VitalPBX

**Why consider it:**
- Easier UI than some traditional Asterisk systems
- Based on Asterisk
- Good feature set out of the box
- Suitable for SMBs

**Best for:**
- Smaller logistics companies
- Teams that want a polished admin interface

Website: https://vitalpbx.com/

---

## My recommendation

If you want the safest and most practical option:

### Choose FreePBX with Asterisk

It gives the best balance of:
- Reliability
- Features
- Documentation
- Community support
- Hardware/phone compatibility
- Ease of deployment

For logistics, I would prioritize:
- Call queues for dispatch and support
- IVR for customers, drivers, warehouses, and billing
- Call recording for dispute resolution and training
- Failover SIP trunk or backup PBX
- Mobile softphone support for remote staff
- Integration with CRM/TMS via APIs or webhooks
- Reporting for missed calls, wait times, and agent performance

---

## Suggested deployment

- **PBX software:** FreePBX Distro
- **Server:** On-premise or VPS with backups
- **Phones:** Yealink, Grandstream, or Fanvil SIP phones
- **Softphones:** Zoiper, Linphone, or Acrobits
- **SIP trunks:** At least two providers for redundancy
- **Security:** VPN for remote phones, firewall, fail2ban, strong SIP passwords
- **Backup:** Daily config backups and call recording backup

---

## Short answer

Use **FreePBX/Asterisk** unless you have a very large or multi-tenant VoIP requirement. For most logistics companies, it is the best open-source self-hosted IP-PBX platform.


Which open source self-hosted PBX has the best integration with standard SIP phones?

**FreePBX**, built on **Asterisk**, is generally the best open-source self-hosted PBX for integration with standard SIP phones.

Why:

- **Very broad SIP phone compatibility**: Yealink, Poly, Grandstream, Cisco/Linksys, Snom, Fanvil, etc.
- **Mature Asterisk SIP stack** with wide real-world deployment.
- **Large community and documentation base**.
- **Easy web-based administration** compared with raw Asterisk.
- Supports common PBX features: extensions, voicemail, IVRs, ring groups, queues, call recording, trunks, BLF, transfers, etc.

A few caveats:

- FreePBX is open source, but some convenience modules—such as advanced endpoint provisioning—may be commercial.
- If you want maximum control and do not mind configuration complexity, **plain Asterisk** is the most flexible.
- If you prefer FreeSWITCH-based systems, **FusionPBX** is also a strong option, but SIP phone ecosystem guidance is generally broader around FreePBX/Asterisk.

**Recommendation:** Use **FreePBX/Asterisk** unless you have a specific reason to choose FreeSWITCH/FusionPBX.


What open source PBX platform is best for building custom telephony applications?

For building **custom telephony applications**, the best open-source PBX/platform is usually **FreeSWITCH**.

Why FreeSWITCH is a strong choice:

- Designed as a programmable telephony engine, not just a PBX
- Excellent APIs via **Event Socket Library ESL**
- Supports scripting with Lua, JavaScript, Python, etc.
- Handles SIP, WebRTC, IVR, conferencing, call routing, recording, and media processing well
- Scales better than many traditional PBX-focused systems for custom apps

Good alternatives:

- **Asterisk** — best if you want a traditional PBX with strong community support and easier setup. Good for IVRs, call queues, voicemail, SIP trunks, and custom logic using ARI/AGI.
- **Kamailio** or **OpenSIPS** — best for high-scale SIP routing, SBC-style logic, and carrier-grade signaling, but not a full PBX/media server by themselves.
- **FusionPBX** — a FreeSWITCH-based PBX GUI, useful if you want FreeSWITCH with an admin interface.

My recommendation:

- Choose **FreeSWITCH** if you are building a custom telephony application or platform.
- Choose **Asterisk** if you mainly need a customizable PBX.
- Choose **Kamailio/OpenSIPS + FreeSWITCH** for large-scale SIP infrastructure.


Recommend an open source PBX software with robust REST APIs for CRM integration.

**Recommendation: Wazo Platform**

For an open-source PBX with strong REST APIs for CRM integration, I’d recommend **Wazo Platform**.

### Why Wazo
- **Open source** PBX/UC platform
- Built on **Asterisk**
- Provides extensive **REST APIs**
- Good fit for **CRM integrations**
- Supports call control, users, lines, voicemail, CDRs, call events, contacts, conferences, provisioning, etc.
- Webhooks/event-driven integration available
- More API-friendly than traditional FreePBX-style systems

### Best use cases
- Click-to-call from CRM
- Screen-pop on inbound calls
- Call history and CDR sync
- User/extension provisioning
- Presence and call status integration
- Automated call routing workflows

### Website / Docs
- Wazo Platform: https://wazo-platform.org
- API docs: https://wazo-platform.org/documentation/

### Alternative
If you want maximum flexibility and are comfortable building more yourself, use **Asterisk directly** with:
- **ARI** — REST API for call control
- **AMI** — event/control interface
- **CDR/CEL** — call records/events

But for CRM integration with a cleaner REST API layer out of the box, **Wazo Platform** is usually the better choice.


What open source PBX software should a real estate office self-host?

For a real estate office that wants to self-host an open-source PBX, I’d recommend **FreePBX** as the default choice.

## Best overall: FreePBX

**FreePBX** is a web-based PBX platform built on **Asterisk**. It is widely used, well documented, and practical for small to mid-sized offices.

Good fit for a real estate office because it supports:

- Auto-attendant/IVR: “Press 1 for sales, 2 for rentals…”
- Ring groups for agents or departments
- Voicemail-to-email
- Call forwarding to mobile phones
- Call recording
- Business hours routing
- SIP trunking
- Desk phones and softphones
- Queues for front desk or leasing teams
- Extensions for each agent
- Remote users

If you want something reliable, common, and easy to administer, choose **FreePBX**.

Website: `https://www.freepbx.org/`

## Strong alternative: FusionPBX

**FusionPBX** is another good open-source PBX option, built on **FreeSWITCH**.

Choose FusionPBX if you want:

- Multi-tenant support
- More flexibility for advanced VoIP setups
- Strong performance at scale
- A cleaner architecture for complex deployments

However, it is generally less beginner-friendly than FreePBX.

Website: `https://www.fusionpbx.com/`

## My recommendation

For most real estate offices:

> **Use FreePBX with a reputable SIP trunk provider.**

Host it either:

- On a small on-prem server if you have reliable internet and power, or
- On a VPS if you want easier remote access and better uptime

Pair it with:

- Yealink, Poly, or Grandstream desk phones
- A SIP trunk provider such as Telnyx, Flowroute, Skyetel, ClearlyIP, or VoIP.ms
- Regular backups
- A firewall/VPN
- Failover routing to mobile phones

## Important caution

Self-hosting a PBX means you are responsible for:

- Security updates
- SIP attack protection
- Backups
- Call quality
- E911 configuration
- Internet/power failover
- Compliance with call recording laws

If the office does not have someone comfortable managing servers and VoIP security, a hosted PBX may be safer.

But if you specifically want open-source and self-hosted, **FreePBX is the best starting point**.


Best open source self-hosted IP phone system for a government department

For most government departments, the best open-source self-hosted IP phone system is usually:

## Recommended: FreePBX / Asterisk

**FreePBX** is a web-based PBX platform built on **Asterisk**, one of the most widely used open-source telephony engines.

### Why it is a strong choice
- Mature and widely deployed
- Self-hosted on-premises or private cloud
- Supports SIP phones, SIP trunks, voicemail, IVR, queues, call recording, ring groups, conferencing
- Web-based administration
- Large community and documentation
- Commercial support available via Sangoma if required
- Good compatibility with many IP phone brands such as Yealink, Poly, Cisco, Grandstream

### Best fit
Use **FreePBX** if the department needs a traditional office phone system with:
- Extensions
- Call routing
- Voicemail
- Reception/auto-attendant
- Call queues
- Internal calling
- SIP trunk integration
- Moderate administrative complexity

---

## Strong alternative: FusionPBX / FreeSWITCH

**FusionPBX** is a web interface for **FreeSWITCH**.

### Why consider it
- Better suited for multi-tenant or larger deployments
- Highly flexible routing
- Good scalability
- Strong SIP handling

### Best fit
Use **FusionPBX** if you need:
- Multiple agencies/departments on one platform
- Complex routing
- Hosted-PBX style separation
- Higher call volume

---

## For highly customized environments: Asterisk directly

If you have telecom engineers or Linux/Asterisk expertise, deploying **Asterisk without FreePBX** gives maximum control.

### Best fit
Use raw **Asterisk** if you need:
- Custom call flows
- Deep integration with internal systems
- Minimal web UI exposure
- Full configuration control

---

# My practical recommendation

For a government department, I would choose:

## FreePBX Distro with Asterisk LTS

It offers the best balance of:
- Stability
- Ease of administration
- Open-source foundation
- Broad hardware support
- Available commercial support
- Strong community knowledge

---

# Important government deployment considerations

Before choosing, confirm these requirements:

- TLS/SRTP support for encrypted voice
- SIP trunk provider compatibility
- Emergency calling/E911 or local equivalent
- Call recording retention policy
- Audit logging
- Role-based admin access
- LDAP/Active Directory integration if needed
- Regular security updates
- Backup and disaster recovery plan
- High availability/failover requirements
- Network segmentation/VLANs for voice
- Firewall and VPN restrictions for remote phones
- Compliance with local data protection and records laws

---

# Short answer

**Best overall:** FreePBX with Asterisk LTS
**Best for larger/multi-tenant deployments:** FusionPBX with FreeSWITCH
**Best for custom engineering-heavy deployments:** Asterisk directly


What is the best open source PBX software for a small business?

The best open-source PBX software for a small business is **FreePBX**.

Here is why it is the top choice, along with a couple of notable alternatives:

### 1. Top Recommendation: **FreePBX** (Asterisk-based)
* **Why it’s the best:** It provides a user-friendly web-based GUI built on top of Asterisk (the industry-standard open-source telephony engine).
* **Key Features:** Interactive Voice Response (IVR/auto-attendant), call queues, voicemail-to-email, ring groups, and extension management.
* **Best For:** Small businesses looking for a reliable, feature-rich system with a massive support community and easy setup.

---

### Alternative Options:
* **FusionPBX:** Built on **FreeSWITCH** (a modern alternative to Asterisk). It has a clean GUI and excels at multi-tenant setups and high-call volumes, though it has a slightly steeper learning curve than FreePBX.
* **Issabel:** An Asterisk-based fork of the older Elastix platform. It includes unified communications features out of the box, such as integrated video conferencing and fax-to-email.

**Verdict:** Go with **FreePBX** for the easiest deployment, best hardware compatibility, and largest community support.


Best open-source self-hosted phone system for a 50-person company

The best open-source, self-hosted phone system for a 50-person company is **FreePBX** (built on Asterisk).

### Why FreePBX is the best choice:
* **Ease of Management:** Features an intuitive Web GUI for managing extensions, call routing, IVRs (auto-attendants), and ring groups.
* **Feature-Complete:** Includes enterprise features out-of-the-box (voicemail-to-email, call queuing, conferencing, time conditions).
* **Cost Effective:** Completely free and open-source, though optional paid commercial add-ons (like advanced CRM integration) are available if needed.
* **Large Ecosystem:** Has the largest community and widest hardware/SIP trunk compatibility of any open-source PBX.

---

### Best Alternative:
* **FusionPBX** (built on FreeSWITCH): Better suited if you prefer FreeSWITCH over Asterisk, or if you plan to scale to multi-tenant configurations in the future, though it has a slightly steeper learning curve than FreePBX.


We are a 30 person startup looking to host our own VoIP PBX server on-premises. What open source software should we use?

For a 30-person startup, the top open-source VoIP PBX software recommendations are:

### 1. **FreePBX** *(Top Recommendation)*
* **Underlying Engine:** Asterisk
* **Why use it:** It is the industry standard for open-source PBX. It provides a full-featured web interface on top of Asterisk, making it easy to set up extensions, call routing, IVRs (auto-attendants), and voicemail without needing deep telecom coding knowledge.
* **Best for:** Quick deployment, ease of management, and a massive support community.

### 2. **FusionPBX** *(Best Alternative)*
* **Underlying Engine:** FreeSWITCH
* **Why use it:** It offers a clean web UI over FreeSWITCH, which is known for high stability, excellent media handling, and lower resource consumption.
* **Best for:** Teams looking for a modern architecture or planning to scale significantly in the future.

---

### **Recommendation**
Go with **FreePBX** (via the Official FreePBX Distro, which includes the OS and dependencies in a single installer). It has the lowest learning curve for a 30-person team and native support for almost all IP phone hardware.


Recommend an open source IP-PBX platform for an enterprise with 200 employees.

The top recommended open-source IP-PBX platform for a 200-employee enterprise is **FreePBX** (powered by Asterisk).

### Primary Recommendation: **FreePBX**
* **Why it fits:** It is the industry standard for open-source business telephony. It handles 200 users easily, offers a mature Web GUI, and provides commercial-grade enterprise features out of the box.
* **Key Features:** Interactive Voice Response (IVR), call queues, ring groups, voicemail-to-email, call recording, hot-desking, and softphone integration.
* **Support & Ecosystem:** Backed by Sangoma, it has a massive global community, extensive documentation, and optional commercial add-ons (like CRM integration) if needed.

---

### Strong Alternative: **FusionPBX** (powered by FreeSWITCH)
* **Why consider it:** If you prioritize high call concurrency, multi-tenancy, or prefer the modern FreeSWITCH core over Asterisk.
* **Trade-off:** Slightly steeper learning curve than FreePBX, but offers exceptionally robust performance and stability.

---

### Deployment Guidelines for 200 Users
* **Recommended Specs (VM or Dedicated):** 4 vCPUs, 8 GB RAM, and fast SSD storage (especially if enabling heavy call recording).
* **SIP Trunks:** Pair with a reputable, enterprise-grade SIP trunk provider (e.g., Twilio, Telnyx, Bandwidth) for external connectivity.
* **HA/Redundancy:** Consider running it as a virtual machine on a high-availability hypervisor (like Proxmox or VMware) for failover.


affordable self hosted open source PBX software

Here are the best free and open-source self-hosted PBX software options:

1. **FreePBX** (Most Popular)
   * **Base Engine:** Asterisk
   * **Best For:** Most users wanting a full-featured, user-friendly PBX with a web GUI.
   * **Key Features:** Easy extension management, IVRs, voicemail-to-email, softphone support, and a massive community.

2. **FusionPBX**
   * **Base Engine:** FreeSWITCH
   * **Best For:** Scalability, performance, and multi-tenant hosting.
   * **Key Features:** High capacity, clean web interface, call queuing, music on hold, and robust security via Fail2ban integration.

3. **Issabel**
   * **Base Engine:** Asterisk
   * **Best For:** All-in-one unified communications (PBX, video, chat).
   * **Key Features:** Continuation of the open-source Elastix project; includes call center modules, built-in CRM integration, and video conferencing tools out of the box.

4. **Wazo Platform**
   * **Base Engine:** Asterisk
   * **Best For:** Developers looking for an API-first PBX platform.
   * **Key Features:** Highly customizable, REST APIs, programmable voice applications, and cloud-native architecture.

5. **Asterisk (Standalone)**
   * **Best For:** Advanced users who want raw control without a heavy web interface.
   * **Key Features:** Lightweight, highly customizable via configuration files, powering the majority of open-source telecom systems.

**Recommendation:** Go with **FreePBX** if you want the easiest setup and broadest hardware support, or **FusionPBX** if you prefer FreeSWITCH's performance and architecture.


What open source PBX software do IT administrators actually recommend?

Among IT administrators, the consensus recommendations for open-source PBX software fall into two main ecosystems based on your needs:

### 1. The Standard Default: FreePBX (Asterisk)
* **What it is:** A Web GUI built on top of the **Asterisk** engine.
* **Why admins recommend it:** It is the most widely deployed open-source PBX in the world. It has a massive community, extensive documentation, and native support for almost every SIP phone brand.
* **Best for:** Most small-to-medium businesses (SMBs) looking for a reliable, feature-rich phone system with a standard web interface.

### 2. The Modern Alternative: FusionPBX (FreeSWITCH)
* **What it is:** A Web GUI built on top of the **FreeSWITCH** engine.
* **Why admins recommend it:** Many admins prefer FreeSWITCH over Asterisk for its modern architecture, higher stability under heavy loads, and native multi-tenancy support (running multiple distinct companies on one server).
* **Best for:** Managed Service Providers (MSPs), multi-tenant environments, and admins who find FreePBX bloated or outdated.

### 3. The API-First / Cloud Choice: Wazo Platform
* **What it is:** An API-driven platform built on Asterisk.
* **Why admins recommend it:** It abstracts the complexity of Asterisk into programmable REST APIs, making it ideal for integrating voice into custom applications or modern cloud infrastructure.
* **Best for:** Developers and sysadmins building custom telecom platforms.

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### Summary Advice from IT Admins:
* **Go with FreePBX** if you want something standard, easy to troubleshoot via forum searches, and quick to set up.
* **Go with FusionPBX** if you need multi-tenancy, better performance under high volume, or plan to resell telecom services.


Best open source self-hosted VoIP server for Linux

The best open-source self-hosted VoIP server depends on your specific needs and technical expertise:

### 1. **FreePBX** (Best Overall for Most Users)
* **What it is:** A feature-rich GUI built on top of the Asterisk engine.
* **Best for:** Small to medium businesses or home setups needing an out-of-the-box full PBX system.
* **Why choose it:** Easy to manage via a web browser, supports IVR (auto-attendants), voicemail to email, call routing, and broad phone compatibility. Available as an easy-to-install Linux distro (FreePBX Distro).

### 2. **FreeSWITCH** (Best for Enterprise & High Performance)
* **What it is:** A modern, highly modular multi-protocol software switch designed for audio, video, and text.
* **Best for:** High-concurrency environments, custom VoIP applications, and multi-tenant setups.
* **Why choose it:** More scalable and stable under heavy loads than Asterisk. (Pair it with **FusionPBX** if you need a web GUI).

### 3. **Asterisk** (Best for Developers & Custom Builds)
* **What it is:** The industry-standard framework for building communications applications.
* **Best for:** Developers who want to build a completely custom phone system from scratch.
* **Why choose it:** Massive community support, highly configurable via text files/APIs, and extremely reliable.

### 4. **Kamailio** (Best for Large Scale / Carrier Grade)
* **What it is:** A SIP proxy server built for handling millions of calls.
* **Best for:** Telecom providers, ISPs, and massive enterprise deployments.
* **Why choose it:** Unmatched SIP routing performance and low resource usage (does not handle media processing like voicemail natively; handles traffic direction).

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### **Recommendation Summary:**
* **Want an easy GUI phone system?** Use **FreePBX**.
* **Want a modern, high-performance engine with a GUI?** Use **FreeSWITCH + FusionPBX**.
* **Want to build custom code?** Use **Asterisk**.


What is the most reliable open source PBX software for a call center?

The most reliable open-source PBX software for a call center depends on your specific needs:

1. **VICIdial** (Best for Dedicated Call Centers)
   * **Why:** Built specifically for call centers (inbound/outbound, predictive dialing, agent performance tracking, campaign management). It is rock-solid, battle-tested, and handles heavy call volumes extremely well.

2. **FreePBX / Asterisk** (Best for General PBX + Basic Call Center)
   * **Why:** Asterisk is the industry-standard engine, and FreePBX adds a user-friendly interface. It is extremely reliable for handling inbound queues, interactive voice response (IVR), call recording, and basic call center operations.

3. **FusionPBX / FreeSWITCH** (Best for High Scalability)
   * **Why:** Built on FreeSWITCH, FusionPBX handles higher concurrent call volumes and multi-tenancy better than traditional Asterisk systems, making it ideal for massive enterprise-level call centers.

**Recommendation:** Go with **VICIdial** if you need advanced call center features like predictive dialing and agent management. Go with **FreePBX** if you need a standard business phone system with straightforward call queuing.


We need to deploy a self-hosted IP PBX on a cloud server. What open source software is best?

For most deployments, **FreePBX** is the best choice.

Here is a quick breakdown of the top open-source options based on your specific needs:

1. **FreePBX (Best Overall)**
   * **Base:** Built on Asterisk.
   * **Why choose it:** It has the largest community, extensive documentation, and a feature-rich web GUI. Ideal for standard business telephony, IVRs, voicemail, and easy administration on a cloud server.

2. **FusionPBX (Best for High Scalability & Multi-Tenancy)**
   * **Base:** Built on FreeSWITCH.
   * **Why choose it:** Better performance under high concurrent call loads compared to Asterisk. Excellent if you need to manage multiple separate companies/tenants on a single server.

3. **Wazo (Best for Developers & API Integration)**
   * **Base:** Built on Asterisk.
   * **Why choose it:** Built with an API-first architecture, making it the best option if you need to deeply integrate telephony into existing custom web applications or CRMs.

4. **Asterisk / FreeSWITCH (Best for Full Control)**
   * **Why choose them:** Raw engines without a web GUI. Choose this only if you want to build a completely custom telecommunication application from scratch using configuration files or code.

**Recommendation:** Start with **FreePBX** (via an official ISO or automated cloud script) unless you specifically need multi-tenancy (FusionPBX) or heavy API integration (Wazo).


Top open source PBX options for small office telephony

Here are the top open-source PBX options for small office telephony:

### 1. **FreePBX** (Asterisk-based)
* **Best for:** General small business use; most popular option.
* **Why choose it:** It provides a user-friendly web interface for Asterisk (the industry standard engine). It has a massive community, extensive documentation, and supports virtually all standard SIP phones and features (IVRs, voicemail-to-email, call queues).

### 2. **FusionPBX** (FreeSWITCH-based)
* **Best for:** High performance, stability, and multi-tenant setups.
* **Why choose it:** Built on FreeSWITCH, it handles media and high call volumes exceptionally well with lower resource usage. It offers a clean web interface for managing calls, auto-attendants, call recording, and faxing.

### 3. **Issabel**
* **Best for:** Unified Communications (voice, video, chat, call center).
* **Why choose it:** An open-source continuation of Elastix (Asterisk-based). It bundles telephony with built-in CRM integration, video conferencing, web chat, and call center management out of the box.

### 4. **VitalPBX**
* **Best for:** Modern UI and easy setup.
* **Why choose it:** Offers a sleek, highly intuitive web interface on top of Asterisk. It includes strong built-in security features (fail2ban, firewall rules) and mobile app integration. *(Note: The core PBX is free/open, though some advanced add-ons are paid).*

### 5. **Asterisk or FreeSWITCH (Raw)**
* **Best for:** Technical teams with developer resources.
* **Why choose it:** If you don't need a pre-packaged GUI and want to build a completely customized, programmable phone system from scratch.

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### **Quick Recommendation:**
* **Easiest path with maximum support:** Choose **FreePBX**.
* **Best performance/modern architecture:** Choose **FusionPBX**.

*(Note: To connect any of these systems to the outside phone network, you will need a **SIP Trunk provider** like Twilio, Telnyx, or Voip.ms).*


Which open source self-hosted phone system software has the best web admin interface?

**VitalPBX** is widely considered to have the best, most modern, and intuitive web admin interface among open-source/self-hosted phone systems. It provides a clean, responsive GUI built on top of Asterisk, making it much easier to navigate than older alternatives.

Here is a quick breakdown of the top options:

1. **VitalPBX** (*Best overall UI*): Clean, modern, highly organized, and mobile-friendly. Offers a generous free tier with optional paid add-ons.
2. **FreePBX** (*Most popular & feature-rich*): The industry standard with the largest community, but its web interface is notoriously dated and complex.
3. **FusionPBX** (*Best for multi-tenant*): Based on FreeSWITCH. Has a straightforward, functional interface that is cleaner than FreePBX, though less visually polished than VitalPBX.

For the modern user experience, **VitalPBX** is the top choice.


We want to replace our legacy PBX hardware with self-hosted open source software. What are our best options?

Here are the top self-hosted, open-source PBX options available, categorized by their best use cases:

### 1. FreePBX (Asterisk-based)
* **Best for:** Most standard business replacements looking for a turn-key solution.
* **Why choose it:** It is the most popular open-source PBX GUI in the world. It provides a web-based interface on top of Asterisk, offering enterprise features like IVRs, call queues, voicemail-to-email, and extensive SIP trunk compatibility.

### 2. FusionPBX (FreeSWITCH-based)
* **Best for:** High-volume calling, high availability, and multi-tenant setups.
* **Why choose it:** Built on top of FreeSWITCH, FusionPBX is faster, more scalable, and handles concurrency better than Asterisk-based options. It is ideal if you plan to manage multiple sites or clients from a single installation.

### 3. Issabel (Asterisk-based)
* **Best for:** Organizations wanting a full Unified Communications (UC) suite out of the box.
* **Why choose it:** A community-driven continuation of the former Elastix project. Beyond standard PBX functionality, it integrates video conferencing, web chat, and call center management features in a single deployment.

### 4. Wazo (Asterisk-based)
* **Best for:** Developers and teams needing an API-first approach or custom web/mobile app integrations.
* **Why choose it:** Wazo is designed for modern infrastructure, offering REST APIs to programmatically control your telephony platform and integrate directly with custom CRMs or workflows.

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### Summary Recommendation
* **Easiest transition with the largest community:** Choose **FreePBX**.
* **Best performance and enterprise scalability:** Choose **FusionPBX**.