SIP trunks: keep your phone system, lose the old lines
Connect your existing on-site phone system to the internet with SIP trunks, ready for the ISDN and analogue switch-off.
- Works with most phone systems
- Keep your numbers
- Pay only for the call capacity you need

What is a SIP trunk?
A SIP trunk replaces ISDN or analogue lines with an internet connection between your phone system and the phone network. Your handsets and phone system stay the same; only the lines change.
Each trunk can carry several calls at once, so you size it to your busiest times rather than paying for a line per call.
Why switch to SIP trunks
Ready for the switch-off
No reliance on ISDN or copper lines.Lower line costs
Replace line rental with call capacity you choose.Disaster recovery
Divert calls elsewhere if your site goes offline.SIP trunk questions
Will SIP work with my phone system?
Most phone systems from the last 10 to 15 years support SIP, sometimes with a small adapter. Tell us the make and model and we will check.
Should I choose SIP trunks or a hosted system?
If your phone system is recent and works well, SIP trunks make sense. If it is old or costly to maintain, a hosted VoIP system is usually simpler.
Ready before the switch-off
Try a VoIPer phone system free for 14 days, or talk to our team on 0800 33 22 66.