United Kingdom Phone Number Format
United Kingdom phone numbers use the country code +44. A United Kingdom mobile number is 10 digits and is written 07400 123456 nationally, or +44 7400 123456 in international format. In E.164 (the format APIs expect) it is +447400123456, with no spaces or leading zero.
| Country | United Kingdom |
|---|---|
| Country calling code | +44 |
| Example mobile (national) | 07400 123456 |
| Example mobile (international) | +44 7400 123456 |
| Example mobile (E.164) | +447400123456 |
| National number length | 10 digits |
Validate a United Kingdom phone number
How to format a United Kingdom phone number
- Start from the national number as written locally: 07400 123456.
- Drop the leading trunk digit (the national prefix, usually a leading 0) if present.
- Add the country code +44 in front to dial from abroad: +44 7400 123456.
- For APIs, SMS, and storage, use E.164, no spaces or dashes: +447400123456.
Frequently asked questions
What is the country code for the United Kingdom?
The international calling code for the United Kingdom is +44. You add it before the national number (dropping any leading 0) when dialing from abroad, for example +44 7400 123456.
How many digits is a United Kingdom phone number?
A United Kingdom mobile number has 10 digits in its national significant number (the part after the +44 country code). Example: 07400 123456.
How do I write a United Kingdom number in E.164 format?
E.164 is the international standard most APIs and SMS gateways require: a plus sign, the country code, then the national number with no spaces, dashes, or leading zero. For the United Kingdom that looks like +447400123456.
How can I check if a United Kingdom phone number is valid?
Paste the number into the validator above. 1Lookup parses it, checks it against the United Kingdom's numbering rules, and returns its line type and carrier so you know whether it is real and reachable.