UK SIP Trunk Provider
UK network you can route on, not a reseller stack
didlogic runs UK voice traffic through on-shore infrastructure, direct carrier relationships and our own autonomous system. You get a UK SIP trunk built for production traffic, not a reseller path hidden behind a generic cloud voice product.
- 3–4 ms ping in London from Telehouse North
- 10–20 ms nationwide from BT Cardiff
- Direct routes to UK fixed and mobile networks, with no aggregator hops
- G.711 end-to-end, with no transcoding to G.729
- Carrier-grade availability backed by 24/7 monitoring
UK SIP trunk use cases
High ASR to UK fixed and mobile, sub-second PDD, no concurrency limits, custom CLI rotation on verified accounts. Predictive dialing supported, with guidance to align with Ofcom persistent-misuse rules. SIP REFER for warm transfers. Hundreds of on-shore and off-shore UK call centre deployments running on the trunk today.
UK termination and DIDs that connect to Retell, Vapi, ElevenLabs, LiveKit, Bland AI and Synthflow via Bring Your Own Carrier. Local London routing keeps real-time round-trip latency low for conversational agents.
Buy a London 020 or any UK geographic number, point it to your SIP endpoint, a mobile, or a forwarding destination. No UK office required. Calls receive proper UK Caller ID presentation. For teams that don’t need a full SIP trunk, see our UK virtual landline option.
didlogic as your UK upstream. Wholesale rate ladder, A-number handling, white-label DIDs, voice peering available at the data centre level.
| didlogic | Typical UK SIP trunk | |
|---|---|---|
| Routing policy | Tier 1 only | Mixed Tier 1 and grey |
| Codec end-to-end | G.711 throughout | Often transcoded to G.729 |
| Concurrent channels | Unlimited | Per-channel pricing |
| UK PoPs | Telehouse London + BT Cardiff | Single London site |
| Custom Caller ID | Passthrough on verified accounts | Often blocked |
| Network ownership | Own AS13006, own hardware | Resold over an underlying carrier |
| Onboarding | 30-day no commitment, free test DID, up to $100 in free credits | Sales-gated, multi-year contracts |
How UK SIP trunk setup works
Get free credits and request a UK test DID if needed.
Use SIP credentials or IP authentication to connect your PBX, SBC, dialer or AI voice platform.
Validate audio quality, PDD, ASR, CLI presentation and route stability with a controlled traffic slice.
Move your UK numbers through didlogic’s paperless porting workflow.
Cut over production traffic once testing is complete, with no per-channel fees and no long-term commitment required.
SIP trunk compatibility
Asterisk, FreeSWITCH, 3CX, FreePBX, Cisco Unified CME, Avaya IP Office, Nortel, and most other SIP-based PBX products.
Retell, Vapi, ElevenLabs, LiveKit, Bland AI, Synthflow.
G.711 u-law and a-law, G.722 HD voice, GSM, G.729.
Self-serve your SIP credentials or IP authentication instantly from the didlogic portal. Provisioning is real-time, meaning you can start routing calls in minutes.
SIP TLS for signalling, SRTP for media.
The UK is one of seven countries where didlogic offers fully electronic number porting. Submit a port request from the self-service portal, we drive the carrier-side workflow, you keep your existing UK numbers with zero downtime on cutover.
Openreach retires the UK PSTN on 31 January 2027. ISDN30, ISDN2 and analogue business lines stop working on that date. Teams still on legacy infrastructure need an IP-based replacement well before the cutover. didlogic UK SIP trunks plug into existing on-premise PBXs or sit behind hosted systems. Bring your existing UK numbers via paperless porting and keep them through cutover day.
Our clients
FAQ: UK SIP Trunk
Do you charge per channel?
No. Send 10 concurrent calls or 10,000. You pay only for minutes.
Can I port my existing UK numbers?
Yes. The UK supports paperless porting. Most ports complete in 5 to 10 working days with zero downtime on cutover.
Do you support custom Caller ID on UK outbound calls?
Yes, on verified business accounts at Plus level and above. We require proof of address before enabling Caller ID passthrough.
Do you support predictive dialing on UK trunks?
Yes. Predictive dialing is supported. We recommend reviewing Ofcom guidance on persistent misuse and silent call rules when setting your dialer’s abandon rate.
What is the typical PDD on UK calls?
0.3 to 1.5 seconds to UK ringback.
Where are UK calls homed?
SIP signalling and RTP media flow through Telehouse London or BT Cardiff. Voice traffic is routed locally to UK Tier 1 carriers without leaving the country.
Do you support SIP TLS and SRTP?
Yes. Both are available for signalling and media encryption.
Do you offer 0800 inbound numbers?
Yes. 0800 Freephone DIDs from $0.99/month with high inbound channel capacity.
Which AI voice platforms work with your UK SIP trunks?
Retell, Vapi, ElevenLabs, LiveKit, Bland AI and Synthflow are supported via Bring Your Own Carrier.
Is there a free trial?
The account is live from signup with free credits, no payment required. Add a free test DID on request. No commitment for the first 30 days.
What is the difference between UK SIP termination and UK DID numbers?
UK SIP termination is used for outbound calls to UK fixed, mobile, toll-free and NGN destinations. UK DID numbers are inbound numbers that let customers call you on a local, national or toll-free UK number.
Can I use didlogic as a backup UK SIP trunk?
Yes. You can route a traffic slice, backup route or overflow traffic through didlogic before moving full production volume.
Do I need a UK company to buy UK numbers?
No UK office is required for many UK geographic number use cases, but account verification and number-use requirements may apply.
Free test DID on request, no payment required, no commitment for 30 days.