Still not filed your self-assessment tax return? Make the midnight deadline to avoid a £100 fine - though the taxman will be lenient if you have a genuine excuse

The clock is ticking for the self-employed and others who need to complete a self-assessment tax return by midnight tonight (31 January 2023).

Around 2.7 million people were still yet to file a tax return for the 2021-22 tax year as of 26 January, according to HMRC.

Those expected to file a tax return include self-employed workers, landlords, higher earners paying back child benefit or claiming additional pension tax relief, and people who receive a foreign income.

Those who miss the 31 January deadline face a £100 fine. And then:

• After three months, a £10 daily penalty is added, up to a maximum of £900. 
• Tax returns that are more than six months late incur further penalties: whichever is greater out of 5% of the tax due or £300 is charged.
• After one year, another 5% or £300 fine is added.

In addition, there’s a hefty 6% daily interest charge for those paying their tax bills late. 

“Paying your tax bill late this year will cost over double in interest charges as HMRC’s official rate of interest has gone from 2.75% to 6% in the last 12 months,” notes Nimesh Shah, chief executive of the accountants' Blick Rothenberg.

But HMRC does say it will treat those with genuine excuses “leniently”, as it wants to focus on those who persistently fail to complete their tax returns and deliberate tax evaders.

Late tax return fine risk

Will the 31 January deadline be extended?

The 31 January deadline has been extended for the past two years, due to the Covid pandemic, which left many people struggling to complete their accounts, and accountancy firms experiencing widespread staff shortages.

HMRC told The Money Edit that there are “no plans to extend the filing and payment deadline” this year.

Shah advised those who haven’t yet filed their 2021-22 return to act quickly and submit their return and pay their tax by 31 January to avoid being slapped with “unpleasant” late filing penalties and interest.

He added: “They need to get organised and gather the information they may need. They may also need to request information from their bank, pension provider or an employer, so they should act now.”

What are the penalties for missing the deadline?

Self-assessment customers need to file their online tax return and pay any tax owed by midnight on Tuesday, 31 January. 

Customers who provide a reasonable excuse before the 31 January deadline can avoid a penalty. Examples of reasonable excuses include an unexpected stay in the hospital, your computer breaking down and unexpected postal delays.

For more examples, have a look at our self-assessment guide.

For tips on how to fill in a tax return, how to pay your tax bill, what you can claim for, and common mistakes, read our self-assessment guide.