Despite extensive coverage of an extension to the self assessment deadline, HMRC has confirmed that the midnight deadline tonight still stands for online filing for self assessment (SA) tax returns.

In exceptional circumstances, where individual taxpayers have complied with all the SA registering requirements and for some reason, for example, their PIN does not work, they will be able to file their return later as long as they contact HMRC today and pay their tax by the midnight deadline of 31 January 2014.

This extension does not apply to tax agents acting for clients.

HMRC confirmed that 'this is not a deadline extension, and only applies in very specific circumstances. Where someone has already registered for self assessment, but has, for example, lost their online activation PIN they would not get another online PIN in time to file at midnight tonight. Because we don't want to give those people a penalty - they are trying to do the right thing after all - providing they have registered for self assessment already and pay their tax due before midnight on 31 January, we would allow them some extra time to receive their online PIN and get their return in. However, in such a case, that person must have registered for self assessment already and pay their tax on 31 January as normal'.

This is not new and has been part of the self assessment process for 20 years, according to HMRC. Any change to the deadline would require a legislative change by parliament.

An HMRC spokesman said: 'We haven't extended the deadline - the tax is still due by midnight tonight. After 31 January you're late, but we don't want to charge penalties, as the most important thing is we get the returns in. If someone has, for example, lost their code and/or pin and realise they have left it too late, we'll allow a bit of extra time to get a new PIN - but the tax will still be due at midnight.'

The exemption applies to two categories of individuals -those who enrolled for the self assessment online service between midnight on 21 January and midnight on 31 January 2014, and those who requested a replacement user ID or password during the same time period. In both cases, individuals would need to wait to receive two letters from HMRC before they could activate their online account. The filing deadline for this limited group of affected individuals will be 15 February.

Following publicity about the self assessment as a result of the changes to child benefits, HMRC told Accountancy that a record volume of filing pre-deadline - at 3pm today 9.55m online tax returns had been submitted. 'This is a record, there are only 800,000 outstanding,' added HMRC spokesperson. Earlier in the week, 1.6m returns were outstanding.

Any affected taxpayer who receives a fine will need to appeal to avoid the payment. Chas Roy-Chowdhury, ACCA head of taxation, warned: 'Individuals who qualify for the exemption will be able to appeal against the automatic £100 penalty charge for a late return, but need to be careful to ensure they meet the new deadline as additional daily penalties will fall due three months later, increasing further if there is no settlement within six months.

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