Quick answer: Yes. If you joined MTD for Income Tax in April 2026, you still have to file your 2025/26 tax return and pay any tax due by midnight on 31 January 2027. Making Tax Digital began with the 2026/27 tax year, so it doesn’t replace the return for the year before.
Many sole traders and landlords make the same assumption. They’ve sent a Making Tax Digital quarterly update, their software looks tidy and it feels like everything is done. Then January arrives with a return they didn’t know was still coming.
We are a London accountancy and tax practice, and this guide covers how the Self Assessment 31 January 2027 deadline fits alongside MTD. If you’d like our accountant and tax specialist team to check your position, call 0207 183 5956.
Key takeaways
- Your 2025/26 tax return (6 April 2025 to 5 April 2026) is still due by 31 January 2027.
- Any 2025/26 tax is due on the same day, plus a possible first payment on account.
- 2026/27 is your first MTD year and ends with a final declaration due 31 January 2028.
- A late return costs £100 straight away.
- A quarterly update doesn’t replace the 2025/26 return.
Do I still need to file a tax return if I’m in MTD for Income Tax?
Yes, for 2025/26. MTD for Income Tax applies from 2026/27 for people with qualifying income over £50,000, so the year that ended on 5 April 2026 follows the traditional Self Assessment route.
Think of it as a handover. 2025/26 is the last year of the old system. 2026/27 is the first year of the new one. For one winter, you have a foot in each.
The confusion is understandable. Much of the commentary says MTD “replaces Self Assessment”, which is true going forward but not for the year just ended. If you’re still getting to grips with the rules, our guide to how to sign up for MTD for Income Tax and our piece on which type of filer you are are good places to start.
What’s the difference between the 2025/26 tax return and MTD for 2026/27?
The 2025/26 tax return is one annual report filed after the year ends. MTD for 2026/27 means digital records, four quarterly updates and a final declaration. Both run side by side this winter.
| 2025/26 (old system) | 2026/27 (MTD) | |
| Period | 6 Apr 2025 to 5 Apr 2026 | 6 Apr 2026 to 5 Apr 2027 |
| How you report | One Self Assessment return | Four quarterly updates, then a final declaration |
| Deadline | 31 January 2027 | 7 Aug, 7 Nov, 7 Feb, 7 May, then 31 January 2028 |
| Tax due | 31 January 2027 | Set by your final declaration |
For what goes into each update, see our line-by-line guide to what to include in an MTD quarterly update.
What are the key tax return deadlines between now and February?
Four dates matter most: 7 November, 31 January, 7 February and 7 May. The tax return deadline of 31 January is the only one that carries both a filing and a payment.
| Date | What’s due |
| 7 November 2026 | MTD second quarterly update (6 April to 5 October) |
| November to December | Best window to prepare your 2025/26 return |
| 31 January 2027 | 2025/26 online return, balancing tax and first payment on account |
| 7 February 2027 | MTD third quarterly update (6 April to 5 January) |
| 7 May 2027 | MTD fourth quarterly update |
| 31 January 2028 | Final declaration for 2026/27 |
Notice how close 31 January and 7 February are. Two filings in one week is where mistakes happen. If your second update is still outstanding, read our guides on the Q2 deadline falling on a Saturday and what 7 November means if you signed up in September.
The paper return deadline (31 October 2026) and the registration deadline (5 October 2026) have both passed. If either affects you, speak to a tax adviser now.
What do I need to file my 2025/26 return?
You need your income and expenses for 6 April 2025 to 5 April 2026, plus any other taxable income. Gathering this first makes the return much quicker.
- Business or rental income and expenses for the full 2025/26 year
- Bank interest and dividend statements
- Pension contributions and Gift Aid payments
- Your Government Gateway login and Unique Taxpayer Reference
- Details of any sales, new properties or business changes
File early if you can. An early return tells you your bill, helps your cash flow and keeps January clear for the 7 February update. If you file by 31 January 2027, keep your records until at least the end of January 2032. You can usually amend a 2025/26 return until 31 January 2028.
If you have rental income as well as trading income, our guide on rental income and self-employment under MTD explains how the two sit together. Joint owners should also read about splitting joint rental income.
How much will I pay on 31 January 2027, including payments on account?
You’ll pay any balance of 2025/26 tax, and you may also make your first payments on account towards 2026/27. Each payment on account is generally half of your previous year’s bill.
Here’s an illustration. Say your 2025/26 bill is £6,000 and you made no advance payments. On 31 January 2027 you’d pay £6,000, plus a first payment on account of £3,000. That’s £9,000 in one go, with a second £3,000 instalment following on 31 July 2027.
This catches people out because the second amount is an advance for a year that isn’t finished. Payments on account generally apply when your bill is over £1,000. If your income has fallen, you may be able to reduce them, but you need to ask before the deadline.
Remember that a quarterly update isn’t a payment. It reports income and expenses, and your tax is paid on the Self Assessment dates. Our post on reading your first MTD tax estimate shows why the estimate in your software isn’t a bill. For planning ideas, see our tips to save tax.
What happens if I file my 2025/26 tax return late?
You’ll face an automatic £100 penalty the day after the deadline, even if you owe no tax. After three months, daily penalties of £10 can build up to £900, and further penalties apply at six and twelve months. Late payment brings separate penalties and interest.
HMRC doesn’t weigh how busy you were. Penalties are automated, and our article on who is watching your HMRC deadlines explains why.
This is where the soft landing causes confusion. For 2026/27, HMRC isn’t applying penalty points for late quarterly updates. That relief doesn’t cover the 2025/26 return. See our guides on MTD penalty rules for 2026/27 and a real MTD penalty example. If HMRC has already written to you, read what to check after an HMRC letter about a missed update.
Could my 2025/26 return put me into MTD from April 2027?
Yes. If your qualifying income from self-employment and property was over £30,000 in 2025/26, you are expected to join MTD for Income Tax from 6 April 2027. Income over £20,000 based on 2026/27 brings in the next group from April 2028.
So your return doubles as a readiness check. If you might be in scope, start choosing software and tidying records now. These guides will help:
HMRC has said it plans to pause MTD sign-up activity around the 31 January deadline and resume afterwards. A quiet January doesn’t mean you’ve been forgotten.
What mistakes should I avoid?
The five biggest are assuming MTD replaced the return, waiting until the last week, forgetting payments on account, mixing up tax years and treating a quarterly update as a tax calculation.
- Assuming MTD replaced your return. It did for 2026/27, not 2025/26.
- Waiting for the last week. HMRC’s online services are busiest then.
- Forgetting that filing and paying are separate. A filed return with no payment still creates a problem.
- Mixing up the years. Keep 2025/26 and 2026/27 records apart. Our MTD quarterly compliance checklist helps you stay organised.
- Treating the quarterly update as your bill. It’s a summary, not a calculation.
Should I use an MTD accountant in London for this?
It isn’t compulsory, but handling a return and quarterly updates in one winter is where errors creep in. A London accountant can coordinate both, plan your January payment and check whether you’re in scope for 2027.
Brayan & Spencer Associates Limited is a London accountancy and tax practice. Our taxation team helps sole traders, landlords, contractors and directors with Self Assessment and Making Tax Digital. Landlords can also see our property tax accountant service and our London landlord MTD survival guide. If HMRC has opened an enquiry, visit our HMRC tax enquiry page.
Browse more in our Making Tax Digital category or Self Assessment category.
Need your Self Assessment 31 January 2027 return sorted before the rush? Call 0207 183 5956 or contact our London team, and we’ll tell you what you owe, when and how to pay it.
Frequently asked questions
Yes, for 2025/26. That return covers 6 April 2025 to 5 April 2026 and must be filed online by midnight on 31 January 2027, even if you’ve already sent quarterly updates for 2026/27.
It stops for your first MTD year. For people who joined in April 2026, 2026/27 ends with a final declaration due 31 January 2028.
No. They relate to 2026/27 and summarise income and expenses for that year. They don’t file or replace the earlier return.
An immediate £100 penalty after 31 January 2027. After three months, daily penalties of £10 can reach £900, and further penalties and interest can follow.
No. Your 2025/26 balance and any first payment on account are due on 31 January 2027.
Yes. Many people file in November or December to know their bill in advance. Early filing doesn’t change the payment date.
