FreePBX / Asterisk
The free, open-source PBX on Asterisk: total control and zero licence cost, in exchange for owning security, patching and every integration yourself.
FreePBX 17 (Debian 12, Asterisk 22) is the reference self-hosted PBX: download it, run it on your own VM or a UK host, pair it with any UK SIP trunk, and pay nothing for the core. Sangoma sells commercial module bundles (Starter $169/yr, Advanced $579/yr or $1,149 for 25 years), support credits and the managed PBXact variant; UK hosts such as freepbx.uk offer managed instances from £15 a month.
The API is GraphQL/REST through the API module with Asterisk's ARI/AMI underneath: powerful but DIY, and there is no MCP. The cost is operational: you own security (CVE-2025-64328 was exploited as a zero-day in December 2025 and 900+ instances were still compromised two months later), emergency routing is a manual outbound route, and many "expected" features are paid modules. Trustpilot has too few reviews to be meaningful.
Pros
- +Zero licence cost and full control
- +Enormous Asterisk ecosystem
- +Perpetual (25-year) module licences available
Cons
- −You own security and patching: a 2025 zero-day left 900+ instances compromised
- −"Not so free" once commercial modules stack up
- −No vendor-run UK cloud; manual 999 routing
Pricing
Minimum commitment: Free (no licence cost). The least you can spend before walking away; excludes numbers, minutes and add-ons.
FreePBX core
$0/yr · annual commitment
Month-to-month: not published
- ✓GPL, free
Sangoma Advanced bundle
$579/yr · annual commitment
Month-to-month: not published
- ✓9 commercial modules; $1,149 for a 25-year licence
UK managed hosting (freepbx.uk)
£15/mo · annual commitment
Month-to-month: not published
- ✓Nano tier; up to £120/mo
Specifications
| Rating | 3.2 |
| Pricing and plans | |
|---|---|
| Month-to-month (entry plan) | Free |
| Annual commit, per month | Free |
| Minimum commitment* | Free |
| Min seats | 1 |
| Commitment for annual rate (months) | 0 |
| Features | |
| Deployment | On-prem PBX |
| Sales model | Direct |
| Integrations and developers | |
| Public API | ✓ |
| MCP server | No |
| Integrations | CRM Link (paid module), Microsoft Teams via SBC, Community modules |
| Support | |
| Emergency 911/999/112 | No |
*How we calculate minimum commitment. Headline per-user prices hide the real cost of trying a platform. Total cost of ownership is licence × seats × term, plus usage, add-ons, setup fees and any early-exit charges. Our "minimum commitment" figure is the floor of that: the entry plan's committed rate × the minimum seats the vendor will sell × the months you must commit to (one month at the month-to-month rate where there is no commitment; the licence price where it is sold per year). It deliberately excludes usage, add-ons and prerequisite licences, so your real first bill will be higher, but never lower than this. For Teams Phone the excluded prerequisites are the Microsoft 365 and Teams licences.
Researched and drafted with AI assistance; reviewed and approved by Dariia Panchenko. How we use AI
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