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.
How we testFreePBX 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 |
| Month-to-month (entry plan) | Free |
| Annual commit, per month | Free |
| Minimum commitment* | Free |
| Min seats | 1 |
| Deployment | On-prem PBX |
| Sales model | Direct |
| Public API | ✓ |
| MCP server | No |
| Emergency 911/999/112 | No |
| Integrations | CRM Link (paid module), Microsoft Teams via SBC, Community modules |
| Commitment for annual rate (months) | 0 |
*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 Tim Meredith. How we use AI