The company blamed the error on "teething problems" with its new pounds 150m centralised billing system and said it would be issuing new bills to all the customers who had been affected. It is hoped that the problem will be resolved by the end of next month.
In East Anglia and eastern England 12,000 customers have received reminders without a bill while in south Yorkshire and the South East, several hundred customers have been similarly affected.
A spokesman for British Gas said that the company had just 18 months to install the new system because the Government brought forward the timetable for opening up the domestic gas market to competition.
"We would have wished under normal circumstances to take considerably longer over putting our system in. But we are not blaming the Government," he said. Previously, more than 60 different computer systems across the country handled customer information and billing.
Shadow consumer minister Nigel Griffiths accused the industry regulator, Ofgas, and the Government of presiding over "chaos", and suggested the Prime Minister set up a ministerial gas consumers' crisis committee "to sort out this mess."Reuse content