How to call United States from United Kingdom

Dialing sequence, step by step

1. 1

   Start with + on a mobile, or 00 when the United Kingdom network requires an all-digit access prefix.

2. 2

   Add 1, the country calling code for United States.

3. 3

   Add the destination national significant number. There is no separate domestic trunk digit to remove. The digit 1 may be used before the ten-digit number for long-distance dialling, but it is also the shared country code in international notation.

Use +1 from a mobile or saved contact. A UK line that requires digits uses 00 before the shared +1 country code and the full ten-digit NANP number.

Mobile and landline examples

X means a subscriber digit placeholder, so these patterns explain the transformation without publishing a private callable number. Save the + format; use the access-prefix format only for a call that starts in United Kingdom.

How the international format is built

E.164 limits the full international number to 15 digits and excludes international and national prefixes. See the E.164 and international-format guide for the reusable structure and regional exceptions.

Common mistakes for this route

• Dropping the three-digit area code; it is part of the required ten-digit NANP destination.
• Treating +1 as unique to the United States even though it is shared by the NANP.

Country code references

Related country-pair guides

• Call United States from Brazil
• Call India from United Kingdom
• Call United States from Japan