More British taxpayers are challenging HMRC over fines it dished out for the late filing of self-assessment forms.

According to Ministry of Justice figures, some 12,100 tax tribunal cases are due to be heard in the 12 months to the end of June, up a quarter from the 9,100 cases in the previous 12 months, the Sunday Times reports.

Despite this, the volume of fines imposed for late payments fell from 1.16m to 850,000, indicating that taxpayers are increasingly set on doing their utmost to avoid being punished by HMRC.

Under the taxman's tough new regime, fines - starting at £100 for taxpayers who missed the January 31 deadline for their 2011-12 online returns - can potentially rocket to £1,600.

It is, however, possible to challenge a fine.

According to HMRC, all appeals must be made in writing and within 30 days of the date of the penalty notice or HMRC decision.

While there are 'no hard and fast rules' HMRC says it may agree to 'a reasonable excuse that prevented you from sending your return on time', such as a life-threatening illness 'that prevents you dealing with your tax affairs', 'unexpected or unforeseeable postal delays' or 'important documents lost, through theft, fire or flood, that can't be replaced in time'.

Another valid 'excuse' is the 'late receipt of your online Activation Code, User ID or password even though you asked for them before the tax return deadline'.

HMC figures reveal that over half a million people sent in tax returns on the final deadline day, leading to a record 9.61m people getting their returns in on time this year, the best performance ever.

With 10.34m people in self-assessment in 2011-12, this means that 93% met the return deadlines, 31 October for paper and 31 January for online.

Of the 9.61m on-time tax returns, a record 83% were sent online. Less than one in five submitted paper returns.