Article
How are self-assessment tax return penalties changing?
From April 2027, automatic time-based penalties for late filing of self-assessment tax returns will be abolished and replaced with a points-based system.
Last updated 29 Jan 2026 | First published 29 Jan 2026
By Helen Wood, CA 2 min read
Making Tax Digital
Self-Assessment Tax Returns
Self Employed
Landlords
What are the current penalties for self-assessment tax returns?
The current penalty regime for late filing of self-assessment tax returns is based on automatic time-based penalties. It starts with £100 for being one day late filing your return. For more details on the automatic fines which follow, see our piece here.
There is a separate penalty regime for overdue payment of income tax. Interest is charged on income tax due from 1st February i.e. one day after the payment deadline. After 30 days, a 5% of tax owed penalty is added as well as interest continuing to accrue. For more details, see our Q&A here.
Thirdly, penalties exist for incorrect tax returns and for failing to notify HMRC that you need to complete a tax return.
What is the new self-assessment penalty regime?
The new penalty regime for late filing will be based on accruing penalty points for certain actions, much like points on a driving licence for traffic infringements. Instead of automatic penalties, you will only receive a fine if you accrue a certain number of points.
Missing the 31st January self-assessment filing deadline would mean you receive one point. After two points you will receive a £200 fine. This means you would only be fined for missing two annual submission deadlines (and not missing one deadline as you would currently) but the fine will be double the current initial automatic penalty of £100.
The Government is also planning to change the penalty regimes for failure to notify and inaccuracy, following its Reform of behavioural penalties consultation in 2025.
Why are the changes happening?
The changes to the penalty regime are to bring the self-assessment penalties in line with the Making Tax Digital (MTD) for income tax penalty mechanisms which have already been announced.
MTD for income tax begins on 6th April 2026 for the first taxpayers (self-employed business owners and landlords who had £50,000 and above qualifying income in 2024/25). It will have a points-based penalty regime covering the quarterly updates required under Making Tax Digital, as well as the end of year final declaration.
No points will be applied for the first four quarterly updates - those for the first intake of taxpayers in the 2026/27 tax year - while the new system is established.
When will the changes take place?
The changes to the self-assessment penalty regime will begin on 6th April 2027. The points-based penalty regime will begin properly for Making Tax Digital for income tax on this date as well.
How can TaxAssist Accountants help?
If you are behind with your tax return filings, TaxAssist Accountants can help you get on top of your tax compliance and give you confidence you can make your filings on time in future. Call us on 01494 718 777 for a free consultation, or use our contact form.
Frequently Asked Questions
If you make a mistake on your self-assessment tax return, you should speak to your accountant. You may also want to discuss it with HMRC to determine whether you need to amend your tax return.
If you do need to amend your tax return, and it is within 12 months of the self-assessment deadline you can change your tax return online. If you need to amend a tax return and this deadline has passed you must write to HMRC setting out the changes and implication to your tax liability.
The deadline for completing a self-assessment tax return is 31st January, when completing this online. If you want to submit a paper tax return, the deadline is 31st October.
There are lots of benefits to getting ahead with your tax return, to find out more visit our self-assessment pages.
Self-employed individuals, partners in business partnerships and landlords may be required to file a tax return. Those in receipt of child benefit and earning over £60,000 and those earning more than £10,000 in savings and investment income will need to complete a tax return too. For a comprehensive list check HMRC’s content on who must send a tax return.
Last updated 29 Jan 2026 | First published 29 Jan 2026
This article is intended to inform rather than advise and is based on legislation and practice at the time. Taxpayer’s circumstances do vary and if you feel that the information provided is beneficial it is important that you contact us before implementation. If you take, or do not take action as a result of reading this article, before receiving our written endorsement, we will accept no responsibility for any financial loss incurred.
Helen Wood, CA
Helen is a qualified chartered accountant (CA) and joined TaxAssist in 2025 following three years as a freelance content writer for clients in the tax and accounting publishing sector. Prior to this, She spent 17 years at Big Four and Top 10 accountancy firms. Helen writes clear and helpful articles on tax and accounting for businesses and individuals.
Choose the right accounting firm for you
Running your own business can be challenging so why not let TaxAssist Accountants manage your tax, accounting, bookkeeping and payroll needs? If you are not receiving the service you deserve from your accountant, then perhaps it’s time to make the switch?
Local business focus
We specialise in supporting independent businesses and work with 100,000 clients. Each TaxAssist Accountant runs their own business, and are passionate about supporting you.
Come and meet us
We enjoy talking to business owners and self-employed professionals who are looking to get the most out of their accountant. You can visit us at any of our 389 locations, meet with us online through video call software, or talk to us by telephone.
Switching is simple
Changing accountants is easier than you might think. There are no tax implications and you can switch at any time in the year and our team will guide you through the process for a smooth transition.