But you must deliver your tax return by hand to Revenue offices before they open on Tuesday for the £100 penalty not to be imposed. If you’re sending your paper tax return by post, it still must arrive by 31 October.

And if your local Revenue office doesn’t have a letterbox and you can't post it through the door, you still could be fined.

Forgotten the new tax return deadline?

This year, HMRC has changed the self-assessment system and there is now only one deadline for paper returns – 31 October – which has been brought forward by three months from 31 January.

But, despite a huge advertising campaign with newsreader Moira Stuart, HMRC is obviously concerned that lots of people are still unaware of the change in deadline; hence the unusual stance of HMRC relaxing the £100 fine.

Previously, HMRC had relaxed the £100 penalty if people who submitted their paper tax returns left them “on the mat” the day after the deadline.

But this is the only time HMRC has given people the chance to submit their paper tax return four days’ late.

John Whiting, from accountants PwC, commented on the extension: "We have always had this to a degree, with a day's grace built in.

"But "on the mat" on Tuesday 4th is taking it publicly a little bit further."

But HMRC stated that there had not been any change to the rules: A spokesman for HMRC said:

"It is a little more complicated this year because of the closure of our offices at 5.00pm and no opening over the weekend.

"It is just that we hopefully this year have spelled it out in a much clearer way, so that there can be no doubt as to when a penalty will be charged or when an inquiry can be opened."

Missed the deadline?

If you have missed the postal deadline or can’t submit your tax return by hand to a local Revenue office, then don’t panic. You can still submit your tax return online and you have three months to do so.

The deadline for online tax returns is 31 January 2009.

But you will only escape the £100 penalty by submitting your tax return online if you haven’t submitted a paper tax return.

If you file your paper tax return late and then submit an online tax return later, you will still be fined for submitting the paper tax return late.

Some taxpayers, such as those who are in charge of trusts, cannot use the online system and may not realise this until the 31 October paper deadline has passed.

For these specific cases, HMRC’s guidance does suggest that they will escape the £100 penalty.

Need more help?

Find out more on how to complete a tax return and the new deadlines and penalties
Ten top tips to filling in your tax return correctly
Going self-employed? Find out when you need to pay tax when you're running your own business
Want to avoid Inheritance Tax? Read our seven steps to saving inheritance tax

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