How to Call a United Kingdom Phone Number from the US

United Kingdom Country Code

The international country code for the United Kingdom is +44. It identifies the UK as the destination of the call and goes after the international access code when you call from the United States.

On a mobile phone, the plus sign can usually replace the US international access code. This means the sequence starts with +44, followed by the UK area code or mobile prefix without its first zero, and then the remaining digits.

The country code is not part of the area code or mobile prefix. Do not add it to a number that you are dialing in domestic UK format. You must first remove the leading zero from that domestic format.

US Exit Code for International Calls

The US exit code for an international call is 011. It tells the phone network that the digits that follow belong to a number outside the United States.

When dialing in the traditional format, enter the sequence in this order:

1. The US exit code: 011.
2. The United Kingdom country code: 44.
3. The UK area code or mobile prefix, with its leading zero removed.
4. The remaining local or mobile digits.

If you are calling from a mobile phone, you can often press and hold the zero key to enter a plus sign. You would then use +44 instead of 011 followed by 44. If that method does not work, use the international dialing instructions supplied by your own carrier.

Step-by-Step: Dialing a UK Landline Number

Start with the UK landline number exactly as it was given to you. A number written for calls within the UK normally has an area code beginning with zero. That zero is a domestic trunk prefix, not part of the international format.

1. Find the area code at the beginning of the UK number.
2. Remove only the first zero from that area code.
3. Dial 011 from a US phone, or use the plus sign on a mobile phone.
4. Enter 44 for the United Kingdom.
5. Enter the area code without its leading zero.
6. Enter the subscriber’s local number.
7. Check the sequence before starting the call.

A safe way to read the completed pattern is: US exit code, UK country code, area code without the initial zero, then local number. Because this page does not provide or verify individual phone numbers, use the number supplied directly by the person or organization you need to reach.

Step-by-Step: Dialing a UK Mobile Phone Number

A United Kingdom mobile phone number is commonly written in domestic form with a mobile prefix that starts with zero. International dialing follows the same leading-zero rule used for landlines.

1. Confirm that you have the complete mobile number from the recipient or another trusted source.
2. Remove the first zero from the domestic mobile prefix.
3. Dial 011 and then 44, or begin with +44 on a mobile phone.
4. Enter all remaining digits in their original order.

The main difference from a landline is what follows the country code. A landline uses a geographic area code, while a mobile number uses a mobile prefix. Do not add a landline area code to a UK mobile number.

If the number is already written with +44, do not add 011 and 44 in front of the entire displayed number. On a mobile phone, dial it as shown. If using a format that begins with 011, replace the plus sign with 011 rather than duplicating the country code.

Reading a UK Phone Number Format

A United Kingdom phone number may be grouped with spaces, parentheses, or hyphens to make it easier to read. These marks are usually formatting aids. The important parts are the country code, the area code or mobile prefix, and the subscriber digits.

Domestic UK formatting often places the area code in parentheses and includes its leading zero. International formatting usually shows +44 and omits that zero. The size of the groups can vary, so do not assume every landline area code has the same length.

When copying a number, keep every digit after removing the one required leading zero. Do not rearrange digits to match a familiar US format. If the grouping is unclear, ask the recipient to provide the number in international format.

Common Dialing Mistakes

• Keeping the domestic leading zero after 44. Remove the first zero from the UK area code or mobile prefix.
• Leaving out the US exit code when dialing from a phone that requires it. Use 011 before 44, or use +44 where the plus format is accepted.
• Entering both +44 and 011. The plus sign replaces the exit code; it does not come after it.
• Confusing 44 with a UK area code. It is the country code and must come before the area code or mobile prefix.
• Adding a geographic area code to a mobile number. A UK mobile number already has its own prefix.
• Removing more than one zero. Only the initial domestic trunk prefix is dropped; other digits stay unchanged.
• Using a number copied from an untrusted directory. Confirm it with the recipient or on the organization’s official contact page.

If the call does not connect, compare the original UK format with your international sequence one part at a time. Check for a duplicated country code, a retained leading zero, a missing digit, or an unsupported international-calling setting.

Call Cost and Carrier Considerations

Before calling, check your own carrier’s official international-calling information. Look for a section usually labeled “International Calling,” “Calling Abroad,” or “Support.” Confirm that international calls are enabled for your line and review how your account handles calls to UK landlines and mobile phones.

Do not assume that landline and mobile destinations are handled the same way. If the carrier’s instructions are unclear, contact its support team through the official account or support page before placing the call.

For a long or important call, also consider the time difference between your location and the recipient’s part of the UK. Confirm a suitable time with the recipient when possible.