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5 Feb 2021

What you need to know if you missed the 2019-20 self-assessment tax return deadline

Find out what charges you may face and the child benefit rules catching people out

Nearly two million self-assessors missed the 31 January deadline to file their 2019-20 tax return, according to HMRC.

The tax authority was expecting to receive 12.1m self-assessment tax returns this year, but only 10.7m were filed by midnight on 31 January. By comparison, 958,296 people missed the filing deadline last year.

This comes after it announced it would waive the £100 late-filing fees throughout February - however, the penalties for paying your tax bill after this date are still in place.

Some of the missing tax returns may also be down to those who don't realise they need to file. An increasingly common reason for this is child benefit claimants who owe tax due to the high-income charge rule.

Here, Which? explains what charges still apply for missing the 31 January deadline and when late tax return penalties will kick in this year, plus whether you need to file a tax return if you claim child benefit.

What late penalties will you pay now?

While the late penalty to file your tax return won't be levied throughout February, the penalty for paying your tax bill late will still kick in if you owed money and didn't pay by 31 January.

Initially, this is 2.6% interest on the tax you owe - but it increases over time.

  • 30 days late (2 March 2021): a charge equal to 5% of the outstanding tax
  • After six months (31 July 2021): a further 5% charge of the outstanding tax
  • After 12 months (31 January 2022): another 5% charge.

There are also penalties for those who filed tax returns with errors or mistakes - but only if HMRC doesn't think you've taken 'reasonable care' filling it out, or if it thinks you're deliberately underestimating the tax you owe.

These penalties are separate, and may be charged in addition to any late fees:

  • No penalty: you've taken reasonable care to fill out your tax return correctly
  • 0-30% of extra tax owing: you've been careless
  • 20-70% of extra tax owing: you've deliberately underestimated your tax
  • 30-100% of extra tax owing: you've deliberately underestimated your tax and have tried to conceal this.

Find out more:late tax returns and penalties for mistakes

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When will late tax return fines be charged?

In normal circumstances, a £100 fine is charged to anyone who files their tax return after midnight on 31 January, with charges quickly increasing the later you submit your return.

However, due to the impact of the coronavirus pandemic, HMRC announced on 25 January that it would waive fines for late tax returns throughout February.

So, while the 31 January deadline remains, you won't get the £100 fine if you file by 28 February.

However, if you miss the February deadline, then the late filing charges will kick in as usual. The late filing penalties work like this:

  • One day late: £100 fine
  • Up to three months late: £10 for each additional day (capped at 90 days), plus £100 fine
  • Six months late: either £300 or 5% of the tax due (whichever is higher), plus charges above
  • 12 months late: another £300 or 5% of the tax due (whichever is higher), plus charges above.

Find out more:how to fill in a self-assessment tax return

Don't get caught out by child benefit tax rules

An increasing number of people are facing fines from HMRC after failing to pay the tax owed from claiming child benefit.

Following a Freedom of Information (FOI) request, HMRC revealed that it's been increasing the number of child benefit compliance checks - both for those who have not registered for self-assessment and should have done, and those who returned the incorrect amount of child benefit.

These checks doubled from 63,591 in 2018-19 to 125,594 in 2019-20 - and, in the case of the 2019-20 checks, 96% of these had tax owing.

Failing to notify HMRC about owing child benefit payment, or paying the wrong amount, can result in a penalty.

When do you have to file a tax return?

You'll only need to file a tax return if you or your partner have an income of £50,000 or more - that's individual income, not joint. HMRC defines a partner as being a spouse or civil partner you're not permanently separated from, or someone you're living with as though they were a spouse.

If this is the case, you'll have to pay the 'high-income child benefit charge' (HICBC), which equates to 1% of the child benefit paid for every £100 of income between £50,000 and £60,000. If you or your partner earn £60,000 or more, you'll have to repay all of the child benefit you've received.

Whoever earns the higher salary will have to make this repayment via a self-assessment tax return, even if they are employed and would usually pay tax via Pay As You Earn (PAYE).

File your tax return with the Which? tax calculator

If you haven't yet filed your 2019-20 tax return, you can still use the Which? tax calculator.

This online tool allows you to tot up your tax bill, suggests allowances and expenses you might have forgotten, and can even submit your return directly to HMRC.

It's easy to use, totally jargon-free and covers a wide range of income sources.