History of telephone numbers in the United Kingdom
Area code City Notes
01 London Until 1990 - see below
021 Birmingham ( 2 = B )
031 Edinburgh ( 3 = E )
041 Glasgow ( 4 = G )
051 Liverpool ( 5 = L )
061 Manchester ( 6 = M )
Introduction of area codes and local dialling codes -- STD codes for director areas
The existing director areas were allocated a short area code , usually in the form 0x1 ( 01 for London ) . These were :
Telephone numbers in the United Kingdom have a structure that reflects their historical demands, starting from many independent companies to a system that supports many different services including cellular phones which were never initially envisaged.