Signal & Syntax · Numbers and formats
What Is a Trunk Prefix?
A trunk prefix is the digit dialed before a national number on a domestic call. The UK uses 0, and the US and Canada use 1. E.164 drops the trunk prefix.A trunk prefix is the digit dialed before a national number on a domestic call. The UK uses 0, and the US and Canada use 1. E.164 drops the trunk prefix.A trunk prefix is the digit dialed before a national number on a domestic call. The UK uses 0, and the US and Canada use 1. E.164 drops the trunk prefix.
Also callednational prefix · trunk code
Example
07911 123456 → +44 7911 123456
Trunk Prefix in Practice
The trunk prefix tells the local exchange the call stays inside the country. The prefix belongs to domestic dialing, not to the number. Writing 0 after +44 produces a number with no route. Removing the trunk prefix is the first fix when converting a list to The trunk prefix tells the local exchange the call stays inside the country. The prefix belongs to domestic dialing, not to the number. Writing 0 after +44 produces a number with no route. Removing the trunk prefix is the first fix when converting a list to The trunk prefix tells the local exchange the call stays inside the country. The prefix belongs to domestic dialing, not to the number. Writing 0 after +44 produces a number with no route. Removing the trunk prefix is the first fix when converting a list to E.164E.164...
Where ScoreMachine Fits
Related Terms
Read the Guide
Guide
E.164 Phone Number Format Explained
The parts of an international number and how to convert a list. Read the guide →Run the Checks on Your Own List
Upload a file in a free workspace, or walk through your use case with our team.