NEW rules governing mobile phone contracts will come into force on January 1 and are predicted to prompt thousands of companies to switch operators during 1999. Dissatisfied customers are to be given the right to change operators without either having to give up their existing phone number - identified as the main reason people stay with a supplier - or pay hundreds of pounds to keep their number.

Mobile phone operators have charged up to £250 per line to transfer numbers to another operator. Under the new legislation this will be free, or at most will involve only a small administrative charge. This will leave businesses free to shop around for the best deal and service without having to undergo the trouble and expense of changing livery and stationary.

A survey by Oftel showed that when offered a better deal only 42% of businesses would change operators if they could not take their mobile numbers with them. But more than 92% would consider changing if they could keep their numbers. The widespread dissatisfaction experienced by many mobile phone users is reflected by the fact that about 30% do not renew their existing contracts when they expire. While a few may decide to relinquish the service altogether, the overwhelming majority switch to another operator.