Tax expert shares what to do if you’ve missed the self-assessment deadline

Millions of Brits were due to file their self-assessment tax return by midnight last night (31 January), with fines imposed from today on anyone who missed the deadline.

Anyone who missed the deadline will need to pay a fixed penalty fee of £100 if they file in the next three months – with the fine increasing if they still haven’t filed by the end of April.

HMRC estimates that more than 12m Britons needed to complete a return for the 2021/22 tax year, with millions still to file just three days before the deadline.

Mike Parkes, tax expert at tax software business GoSimpleTax, today warned people who have missed the deadline to get their return in as quickly as possible. “Being late to file your self-assessment tax return or pay your tax bill carries a standard penalty of £100, with this fine rising if you’re more than three months late. HMRC won’t accept mistakes, forgetfulness or lack of funds as a reason not to have filed your return, so if you’ve missed the deadline you should aim to submit your return as quickly as possible to avoid a higher fine.

“However, there are exceptions for genuine reasons for missing the deadline – such as bereavement, illness or technical failure – but you’ll need to provide evidence of these to escape the fine. If you do have a reasonable excuse for missing the deadline, you should get in touch with HMRC as soon as you can. You’ll still need to file a return, but could escape the £100 fine,” Mike added.

If you are more than three months late filing your return, HMRC can add an extra £10 penalty for each day for the next 90 days. After six months, you may have to pay a further penalty of 5% of the tax you owe or £300 – whichever is greater. You’ll also pay interest on the tax you owe as well as on any fines.

“Tax returns for the current financial year can be filed any time after 5 April 2023, and your tax still won’t be payable until next January, so there’s no reason to delay filing your return. Get the job done quickly and avoid a last-minute panic next January,” he advised.

For anyone worried that they can’t pay their tax bill, Mike advises they get in touch with HMRC as quickly as possible. “This is a scary situation, but most taxpayers can find a resolution directly with HMRC. Get in touch with HMRC as soon as you can; in most instances they will be able to help you set up a payment plan, called a ‘Time to Pay’ arrangement. These plans can be put in place for tax bills of less than £30,000 which you plan to pay off in less than 12 months.

“It’s important to note that these payment plans carry interest and, given the rise in the base rate, it will cost you considerably more to pay this way. It’s therefore very important that you set aside enough money each month for tax - around 20-25% of your income should be plenty.”