As part of a crackdown on tax avoidance in the medical profession, HM Revenue and Customs (HRMC) is offering an amnesty for doctors who may have underpaid tax to rectify the situation.

If they do not notify HRMC by 30 March 2010, GPs found to owe tax on income going back up to 20 years could face a penalty of 100% of the tax owed, on top the debt and any interest on it.

Accountants RMS Tenon said ‘a significant number' of GPs have received a letter from HMRC urging them to disclose unpaid tax, but many may be too busy to reply.

Gary Ashford, a director at RSM Tenon, said the amnesty's deadline fell just as GPs were completing the year's QOF and enhanced services paperwork.

‘[HMRC] has written to all those it feels are a ‘risk',' said Mr Ashford.

‘In other words, those it believes should be making a disclosure based on the information it has collected.

‘Early signs are that not many medical professionals are taking up the disclosure facility offered by HMRC. My concern is that they are so busy focusing on their mountain of paperwork that they have not even considered their position.'

The firm is appealing for the deadline to be extended by a month to 30 April 2010.

‘HMRC's view is that several thousand doctors and dentists are potentially eligible to make a disclosure under the THP. The clock is ticking and medical professionals will simply run out of time,' said Mr Ashford.

• Do you have a financial question? Ask our experts