0044

0044 is the sequence formed by the international dialing prefix 00 followed by the United Kingdom’s country code 44. It is encountered when dialing a United Kingdom telephone number from outside the UK in regions where the 00 prefix is used for international calls. In modern practice, the plus sign (+) followed by 44 is more commonly written and dialed, but 0044 remains a valid international dialing string.

Country code 44 is part of the ITU-T E.164 numbering plan and identifies the United Kingdom for international dialing. The code is used for calls to UK landlines and mobile numbers from abroad. Within the UK, the domestic numbering system uses a leading 0, and international callers omit that 0 when using 44.

Dialing conventions: When dialing a UK number from another country, the international prefix (often 00 or the plus sign) is followed by 44, with the leading 0 in the national number dropped. For example, a London landline typically written as 020 7946 0958 becomes [phone] or 0044 20 7946 0958. A mobile number such as 07 1234 5678 becomes [phone] or 0044 7 1234 5678.

Notes: 0044 is commonly used in dial strings, invoices, and older systems that specify the international prefix explicitly. The +44 form is the standard modern convention, equivalent in function to 0044.