This year (yet again) British Telecom and OFTEL found it necessary to change the area codes for some of the UKs biggest cities, and those of Northern Ireland.

For your easy reference, the changes are listed below

Area          Old Code  Old Number     Changed      New Code New Number
Cardiff        01222      XXXXXX      5 August       029     20XX XXXX
Coventry       01203      XXXXXX     19 August       024     76XX XXXX  
Portsmouth     01705      XXXXXX      2 September    023     92XX XXXX 
Southampton    01703      XXXXXX      2 September    023     80XX XXXX 
London (Inner)  0171     XXX XXXX    14 October      020     7XXX XXXX 
London (Outer)  0181     XXX XXXX    14 October      020     8XXX XXXX 

The Northern Ireland Area Codes have changed totally.