Outline — full article in progress
This page has the structure and introduction. The full article is being written by the network team. In the meantime, ask us directly.
Ofcom requires every call made to a UK number to carry a valid, dialable caller ID that the caller is allowed to use — and UK networks block calls that don't. This article explains what counts as a valid CLI, which number ranges you can present, and what happens to calls that break the rules. For routes and rates, see our UK SIP trunk page.
What Ofcom requires
Valid and dialable numbers
Number ranges you can present
- Geographic 01/02, non-geographic 03, mobile 07