What dialing code is used to call a UK mobile?

UK mobile numbers begin with 074xx, 075xx, 07624 and 077xx through 079xx, which is to say +44 74xx through +44 79xx in international format. Mobile numbers are non-geographic; the same codes are used throughout the country.

Mobile phones from the Isle of Man (technically not part of the UK, but shares country code +44 with the UK and other Crown dependencies) begin with 07524, 07624, and 07924. Mobile phones from Guernsey use 07781, 07839, and 07911. Mobile phones from Jersey use 07509, 07700, 07797, and 07829.

To dial any UK number from overseas, replace the trunk prefix 0 with the country code +44.

If you are calling a UK mobile that happens to be roaming in some other country, you dial it exactly the same way you do when the UK mobile is in the UK. The mobile network automatically re-routes the call, and the roaming mobile user pays any roaming surcharges that may apply.

Mobile numbers in the range 07700 900 000 through 07700 900 999 are reserved for fictitious use in radio, television, and other such purposes.

(The plus sign means "insert your international access prefix here." From a GSM mobile phone, you can enter the number in full international format, starting with the plus sign. The most common prefix is 00, but North America (USA, Canada, etc.) uses 011, Japan uses 010, Australia uses 0011, and many other countries use different prefixes.)