How to Write a Phone Number Correctly (US, UK and International)

For forms and contacts, write numbers in international format: +, country code, then the number without its leading 0, for example +1 212 555 0143.

Formats by use

Rules that work everywhere

• Start with + and the country code when the reader may be abroad.
• Drop the leading 0 after the country code.
• Group digits the way the country does, for readability.
• For extensions, add "ext." and the digits.

On sign-up forms

If the form has a separate country box, choose the country there and type only the national number without the leading 0. Typing the country code twice is a common reason codes never arrive.

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On business cards and websites

For customers in several countries, show the international format with +. On a website, make the number a tap-to-call link so phones dial it directly with the right country code.

FAQ

How do I write a phone number internationally?

Use +, the country code, then the number without its leading 0.

What is E.164 format?

The international format with no spaces, for example +12125550143.

Should I include the 0 after +44?

No.

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