United Kingdom phone number format
United Kingdom phone numbers use the country code +44. A mobile number looks like 07400 123456 inside the United Kingdom and +44 7400 123456 from abroad: the leading 0 is dropped after +44. Mobiles have 10 digits after the country code, and the E.164 form is +447400123456.
United Kingdom number format at a glance
| Country calling code | +44Shared with Guernsey, Isle of Man, Jersey |
|---|---|
| International prefix (calling out of the United Kingdom) | 00 |
| Trunk prefix (domestic dialling) | 0 |
| Mobile number length | 10 digits after +44 |
| Landline number length | 9 or 10 digits after +44 |
| Mobile vs landline from the digits | Yes, separate ranges |
Example United Kingdom phone numbers
These are the example numbers from Google’s libphonenumber data, the same numbering-plan data our validator uses, written three ways.
| Format | Mobile | Landline |
|---|---|---|
| National (inside the United Kingdom) | 07400 123456 | 0121 234 5678 |
| International | +44 7400 123456 | +44 121 234 5678 |
| E.164 | +447400123456 | +441212345678 |
How to write a United Kingdom number in E.164
- Remove spaces, dashes, dots and brackets so only digits are left.
- If the number starts with the trunk prefix 0, remove it. It is only used when dialling inside the United Kingdom.
- Put +44 in front. The result has 10 digits after the country code for a mobile.
So 07400 123456 becomes +447400123456. E.164 is the format SMS gateways, dialers and most CRMs store; see the E.164 format explained for why.
Mobile or landline?
The United Kingdom allocates separate number ranges to mobiles and landlines, so a numbering-plan check reads the line type straight from the digits, for free. That type describes the range the number came from. It doesn’t prove the number is connected today.
Validate a list of United Kingdom numbers
Check a single number with the free phone number validator. For a whole file, upload the CSV to the verifier: every row gets a status, the E.164 number, the country and the line type, and emails in the same file get a live mailbox check. The Email + Phone plan ($49.99 a month) adds 5,000 live carrier lookups a month for the real line type and current carrier.
Common questions
- What is the country code for the United Kingdom?
- The country calling code for the United Kingdom is +44. It is shared with 3 other countries and territories, so the number after it decides which one a number belongs to. When you call the United Kingdom from abroad, dial your international prefix (or +) followed by 44 and the number without its leading 0.
- How many digits is a United Kingdom phone number?
- A United Kingdom mobile number has 10 digits after the country code +44, and a landline has 9 or 10. Written for dialling inside the United Kingdom, a number gains the trunk prefix 0 in front.
- How do I write a United Kingdom number in international format?
- Start with +44, drop the leading 0, then add the rest of the number. The mobile number 07400 123456 becomes +44 7400 123456, or +447400123456 in E.164, the form most CRMs and SMS tools expect.
- Can you tell if a United Kingdom number is a mobile?
- Usually, yes. United Kingdom numbers come from ranges allocated separately to mobiles and landlines, so a numbering-plan check reads the line type from the digits. It tells you what the range is for, not whether the number is in service.
That was one number. Your CRM export has thousands.
This tool checks one number at a time. Cleaning a list means every row in E.164, invalid numbers separated out, and the emails beside them checked too.
- Upload a CSV up to 100,000 rows with an email or phone column
- Every phone gets status, E.164 format, country and line type
- Emails in the same file get a real SMTP mailbox check
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