BRING YOUR OWN PBX
UK trunks for systems you control.
Connect an existing PBX using registration, IP peering or IAX2. Sipflex supplies the UK numbers and calling capacity; your PBX remains yours.
- £2 per number
- One complimentary account channel
- PJSIP, peering and IAX2
- Detailed configuration guides
PRIORITY PLATFORMS
Choose your PBX.
These pages focus on provider settings and known interoperation, with clear boundaries around customer-controlled configuration.
Asterisk
PJSIP registration, IP-authenticated peering and IAX2 with copyable configuration examples.
FreePBX
Current PJSIP and IAX2 guidance for FreePBX administrators managing their own system.
3CX
Registered SIP trunks, pilot-number routing and DDI configuration using the Generic SIP Trunk template.
IAX2
A first-class IAX2 service for Asterisk, FreePBX and compatible open telephony platforms.
ANOTHER SIP PLATFORM?
Generic SIP is welcome.
Sipflex is not limited to the PBXs listed above. If your system supports standard SIP registration or IP peering, you can configure it using the settings shown in your portal.
View generic SIP settings30-DAY FREE TRIAL
Connect your system to Sipflex
Start testing with your own PBX, application or voice platform.
No card required.