UK told to prepare for phone code changes

Offices and homes in London could sound eerily quiet on Monday morning if phone users forget that the London 0171 and 0181 codes are finally cut off this weekend.

From Saturday, all calls made to London using the old codes will fail, with voice calls redirected to an announcement. All calls will require the new 020 code followed by a 7 or 8 depending on the area.

Despite the fact that London numbers officially changed in April, calls have been able to connect using the 0171 and 0181 codes.

According to The Big Number company, the industry group controlling the change, 20 per cent of calls to London are still made using the old codes, many of which it expects are "machine-to-machine" calls where stored numbers have not been updated.

Andrew Lawford, campaign manager for The Big Number, said an estimated five million mobile phone users still have old codes programmed into their handsets. "Callers may not have thought to change these numbers because they tend to be out of sight and out of mind," he said.

UK telecoms watchdog Oftel, which said the code change will meet the country's "ever growing telephony needs for many years to come", has also warned people to check that that they have changed all old codes stored in phones, faxes and computers.

London is the last of six areas where old codes have been switched off, following changes made in April. The other changes took place in Cardiff, Coventry, Northern Ireland, Portsmouth and Southampton.