Businesses in the capital are facing another phone number change with the introduction this summer of the “020 3” prefix.
The 020 3 prefix will be in addition to the 020 7 and 020 8 numbers already used by London businesses and households. Existing numbers will not have to be replaced.
The new prefix has been introduced to help the capital meet the growing demand for new phone lines.
Telecoms regulator Ofcom said 020 3 would be issued to some residential and business customers who put in a new line or applied for a new telephone number from late summer onwards.
This will mean some businesses will have to operate two different code prefixes, which could be confusing for some of their customers trying to contact them.
Larger companies will also have to make minor changes to their private branch exchanges.
A public information campaign has begun today in London and the south-east to explain and promote the new prefix.