Those who miss the deadline will still have their tax calculated by HMRC but the taxman can't promise to have made the calculations before the payment deadline. That could leave some people facing late payment interest and surcharges.

A spokesman for Taxdebts, which aims to help people who have fallen behind with their payments, said:

"A spiralling pattern of delayed tax payments, interest and surcharges can develop, resulting in the tax authorities taking recovery action. This action can involve anything from telephone calls or visits to the business premises by the tax collector or seizing assets.

"The financial burden of tax arrears can lead to business failures in the most serious cases, and even personal bankruptcy."