Who remembers '01' for London? Well, pretty much from the late 1950's up until the 6th May 1990, making a phone call to a London telephone number meant you would have had to have dialled the London telephone code '01', likewise there were other cities within the U.K. where their telephone numbers could have only been reached by using their own unique telephone codes. If a subscriber however was using a telephone within London and was calling another London telephone, the '01' code would not have been needed, just like todays system with '020'. All-figure numbering had been introduced in London from 1966 which meant that the Area Code and the 4 digit telephone number both had to be dialled even if the two telephones were within the same area. The 6th May 1990 saw the unfortunate end to London's '01' telephone code, the main reason for the London code change was simply to be able to allocate new telephone numbers in order to cater for the ever growing demand for them. The new telephone codes to reach London from that date were '071' for Inner London and '081' for Outer London.
Set out below is a reference table showing details of the geographical areas within the London telephone area.

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