Missed The Self Assessment Deadline? Here’s The Fastest Way To Avoid Being Penalised

The Self Assessment tax return deadline has passed, and you might be one of many who missed it. If you did, you’ll have already received an automatic penalty. But there are ways you can sidestep this…

10 Minute Read

Last Updated: 8th February 2022

The Self Assessment tax return deadline has passed, and you might be one of many who missed it. If you did, you’ll have already received an automatic penalty.

But there are ways you can sidestep this penalisation, and any additional fines too. Here, we explain how.

Appeal the automatic penalty

The immediate fine for missing the Self Assessment tax return deadline is £100. This can be appealed against – provided you have a reasonable excuse. HMRC have a list of what they would usually deem acceptable, such as the death of a close loved one, or a serious or life-threatening illness.

Note that you have to send your tax return or tax bill payment as soon as you can once the situation has been resolved. Also be aware that this must be a legitimate excuse. Every year, HMRC publish the most ridiculous (and rejected) claims for not filing the Self Assessment tax return.

Avoid further fines

The instant penalty stands if your tax return is up to three months late. But if you don’t file it within this time frame, or pay the tax owed on time, then you will be further penalised.

Our table below illustrates the additional penalties you would receive.

Late tax return/paymentPenalty
3-6 months after tax return deadline£10 per day
6-12 months after tax return deadline
£300 fine or 5% of the total tax due (whichever is greater)
12 months after tax return deadlineAn extra £300 fine or 5% of the tax you owe (whichever is greater)
30 days after payment due date5% of your total tax bill and interest for this time
6 months after payment due date
Another 5% of the tax due and interest for this period
12 months after payment due dateAn additional 5% of the tax owed, plus interest for this time

To avoid these particular penalties, you’ll need to submit your Self Assessment tax return as soon as you can. If you want to get it done in the quickest way possible, then the best idea is to employ dedicated tax return software – like GoSimpleTax.

Use tax return software

Our tax return tools aren’t just the swiftest method because of their automated functionality. Submitting through GoSimpleTax can also help you avoid miscalculations that could lead to penalties for inaccurate sums, and further strains on your time as a result.

Here’s how our features can help:

  • Automatic calculations – See the tax owed without having to sort the sums yourself, minimising the chance of errors
  • Real-time inputting and calculations – So you don’t have to leave your Self Assessment tax return until January, and have a full view of your financial situation throughout the year
  • Notifications and tax-saving recommendations – The software will alert you when it spots a potential mistake, as well as give you the opportunity to reduce your tax liability where relevant
  • On-the-go functionality – With an app and the ability to upload receipts in an instant, you can work on your tax return wherever you are

So, get your Self Assessment tax return done as soon as possible with GoSimpleTax and reduce the penalties you’ll receive from HMRC. You can even sample some aspects of our software before you decide to upgrade and file your return – we provide a free 14-day trial.

If you have any questions, simply speak to a member of our team. We’d be more than happy to help.

Last updated: 7th February 2020.

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Blog content is for information purposes and over time may become outdated, although we do strive to keep it current. It's written to help you understand your Tax's and is not to be relied upon as professional accounting, tax and legal advice due to differences in everyone's circumstances. For additional help please contact our support team or HMRC.


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