{"meta":{"name":"Country Calling Codes API","apiVersion":"1.2.0","source":"https://countrycalling.codes","documentation":"https://countrycalling.codes/developers","openapi":"https://countrycalling.codes/api/calling-codes/openapi.json","standard":"ITU-T E.164","resultCount":1,"includesDialingGuide":true},"lookup":"gb","countries":[{"name":"United Kingdom","officialName":"United Kingdom of Great Britain and Northern Ireland","code":"GB","code3":"GBR","dialCode":"+44","dialCodeNumeric":44,"region":"Europe","subregion":"Northern Europe","capital":"London","flag":"🇬🇧","trunkPrefix":"0","notes":"Trunk prefix 0 is dropped when dialing internationally.","historicalCodes":[{"code":"+44","from":"1960s","note":"UK assigned +44","sourceOB":"ITU E.164 historical"}],"mobilePrefixes":["^07[1-57-9][0-9]{8}$"],"landlinePrefixes":["^0[12][0-9]{8,9}$"],"mnpStatus":"full","mnpSince":"2000-01-01","mobileIdentificationMethod":"prefix","emergencyNumbers":{"police":"999","fire":"999","ambulance":"999","general":"112","supports112":true,"supports911":false,"euCompliant":true},"timezones":["Europe/London"],"primaryTimezone":"Europe/London","observesDst":true,"iddPrefix":"00","alternateIddPrefixes":[],"dialingGuide":{"status":"published","countryCode":"GB","countryName":"United Kingdom","dialCode":"+44","answer":"The United Kingdom uses country calling code +44. Most UK numbers are written domestically with a leading 0 national prefix. Remove that 0 when converting the number to international format: a London pattern such as 020 7946 XXXX becomes +44 20 7946 XXXX.","trunkPrefixRule":"Remove the national prefix 0 before adding +44. The 0 is not part of the national significant number in international format.","leadingZeroBehavior":"drop","iddPrefix":"00","mobile":{"kind":"mobile","nationalDisplay":"07700 900XXX","internationalDisplay":"+44 7700 900XXX","parts":[{"value":"+44","label":"Country code","meaning":"United Kingdom"},{"value":"7700","label":"Mobile range","meaning":"Example mobile prefix without the trunk 0"},{"value":"900XXX","label":"Subscriber digits","meaning":"Placeholder digits"}],"transformation":"Remove the first 0 from 07700, then add +44."},"landline":{"kind":"landline","nationalDisplay":"020 7946 XXXX","internationalDisplay":"+44 20 7946 XXXX","parts":[{"value":"+44","label":"Country code","meaning":"United Kingdom"},{"value":"20","label":"Area code","meaning":"London code without the trunk 0"},{"value":"7946 XXXX","label":"Subscriber number","meaning":"Placeholder digits"}],"transformation":"Remove the first 0 from 020, then add +44."},"mnpCaveat":"Mobile number portability means a prefix may not identify the current carrier. Treat carrier data as a timestamped lookup result, not a permanent property of the number.","formattingExceptions":[{"title":"Do not write +44 (0)","explanation":"The optional-zero notation is often misunderstood and is not a single dialable format. Store +44 followed by the national significant number without the trunk 0."}],"commonMistakes":["Keeping the domestic 0 and producing +44 020… instead of +44 20…","Dialling 00 44 and also retaining the plus sign.","Treating 070 personal numbers as ordinary mobile numbers."],"reviewedBy":"countrycalling.codes editorial team","lastVerified":"2026-07-19","sources":[{"publisher":"Ofcom","title":"The National Telephone Numbering Plan","url":"https://www.ofcom.org.uk/siteassets/resources/documents/phones-telecoms-and-internet/information-for-industry/numbering/other/national-numbering-plan.pdf?v=401943","lastVerified":"2026-07-19"},{"publisher":"International Telecommunication Union","title":"National numbering plan: United Kingdom","url":"https://www.itu.int/oth/T02020000DD/en","publishedAt":"2025-02-28","lastVerified":"2026-07-19"},{"publisher":"International Telecommunication Union","title":"ITU-T E.164: The international public telecommunication numbering plan","url":"https://www.itu.int/rec/T-REC-E.164-202602-I/en","publishedAt":"2026-02-13","lastVerified":"2026-07-19"}]},"slug":"united-kingdom","url":"https://countrycalling.codes/country/united-kingdom"}]}