Ofcom is launching a public education campaign today about the new London number code 020 3.
Numbers with the new code will be issued to business and home users after 1 June. The new code is being used because 020 7 and 020 8 numbers are running out, and will give telecoms companies another 10 million choices.
"It is important to note that this is not a code change; existing residential and business customers do not need to change their telephone number," said Ofcom in a statement.
The campaign will feature 4,000 adverts on the London underground, and leafleting of public buildings. Unlike existing codes the new numbers will not reflect the user's location.
In 1991 London's codes changed from 01 to 071 and 081, and in 1995 to 0171 and 0181. In 2002 the numbers changed again to 020 7 and 020 8.
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