BlogHMRC Deadlines

HMRC Tax Deadlines 2025/26

Every important date for the 2025/26 tax year, laid out in a clear timeline. Bookmark this page so you never miss a deadline or face a penalty.

8 min read

Tax deadlines wait for nobody. Whether you are a seasoned self-employed person or just starting your self-employment journey, knowing exactly when HMRC expects action from you is essential. Missing a deadline does not just mean a penalty -- it means stress, rushed paperwork, and potentially paying more than you need to.

Below is every key date for the 2025/26 tax year, starting from when the year begins through to the final payment. We have included both traditional Self Assessment dates and the newer Making Tax Digital quarterly update deadlines.

Late Filing Penalties

Miss the 31 January deadline and HMRC charges an immediate £100 penalty -- even if you owe no tax. After 3 months, daily penalties of £10 kick in (up to£900). After 6 months, a further £300 or 5% of tax due (whichever is greater). After 12 months, another £300 or 5%. Late payments also incur interest at the prevailing HMRC rate. The message is clear: file on time, every time.

Complete 2025/26 Tax Calendar

6 April 2025

Tax Year Starts

The 2025/26 tax year begins. From this date, every fare you earn and every business expense you incur counts towards this tax year. If you have not already set up your record-keeping system, now is the time. Start logging income and expenses from day one to avoid the year-end scramble.

5 August 2025

Q1 MTD Update Due

If you are within Making Tax Digital for Income Tax, your first quarterly update is due. This covers 6 April to 5 July 2025. Submit a summary of your income and expenses for the quarter through MTD-compatible software. If MTD does not apply to you yet, this is still a great checkpoint to review your first quarter.

5 October 2025

Register for Self Assessment

If you became self-employed during the 2024/25 tax year and have not already registered, this is your absolute deadline. Register online at gov.uk and you will receive your Unique Taxpayer Reference (UTR) within 10 working days. Late registration can result in penalties, so do not wait until the last minute.

5 November 2025

Q2 MTD Update Due

Your second quarterly update covers 6 July to 5 October 2025. By this halfway point in the tax year, you should have a clear picture of your annual income trajectory. Review your figures and compare with last year -- are your expenses in line? Are you on track with the tax you need to set aside?

31 January 2026

2024/25 SA Deadline & Payment

This is a double deadline for the previous tax year (2024/25). Your Self Assessment tax return must be filed online, and the full tax owed must be paid. If your 2024/25 bill was over £1,000, the first payment on account for 2025/26 is also due. Late filing triggers an automatic £100 penalty, even if you owe nothing.

5 February 2026

Q3 MTD Update Due

Third quarterly update covering 6 October 2025 to 5 January 2026. This quarter includes the busy Christmas and New Year period, which can be a high-earning time for self-employed people. Make sure all that extra income is properly recorded.

5 April 2026

Tax Year Ends

The 2025/26 tax year closes. After this date, no more income or expenses can be attributed to this tax year. Take a moment to do a final review -- have you captured all your receipts? Is your mileage log complete? Now is the time to tie up loose ends before you prepare your return.

5 May 2026

Q4 MTD Update Due

Final quarterly update for 2025/26 covering 6 January to 5 April 2026. After submitting this, you will have sent all four quarterly summaries to HMRC. You still need to complete your End of Period Statement and final declaration later.

31 July 2026

2nd Payment on Account (2024/25)

The second payment on account for 2024/25 is due. This is the other half of the advance payments towards last year's tax. Remember, payments on account are based on your previous year's tax bill, so if your income has dropped significantly you can apply to reduce them.

31 January 2027

2025/26 SA Deadline & Payment

The big one for the 2025/26 tax year. Your Self Assessment must be filed online and the balancing payment made. If your tax bill exceeds £1,000, you will also pay the first payment on account for 2026/27. This is the date every self-employed person works towards.

31 July 2027

2nd Payment on Account (2025/26)

The second payment on account for 2025/26. This completes your advance payments towards the 2026/27 tax year. After this, the 2025/26 cycle is fully closed.

What Is Making Tax Digital (MTD)?

Making Tax Digital for Income Tax Self Assessment (MTD for ITSA) requires self-employed individuals to keep digital records and send quarterly updates to HMRC using compatible software. It is being rolled out in phases:

  • April 2026: Mandatory for self-employed with income over £50,000
  • April 2027: Extended to income over £30,000

Even if MTD does not apply to you yet, adopting quarterly reporting habits now will put you ahead of the curve. Read our full Making Tax Digital guide for everything you need to know.

5 Tips to Never Miss a Deadline

1

Set calendar reminders

Add all the dates above to your phone calendar with reminders two weeks before each deadline.

2

File early

You can submit your 2025/26 return from 6 April 2026. Filing early gives you months to arrange payment.

3

Save monthly for tax

Put 25-30% of your profits into a separate savings account each month. The January bill should never be a surprise.

4

Keep records as you go

Do not wait until year-end. Log income daily and expenses weekly at minimum. Future-you will be grateful.

5

Use Fyled to automate it

Fyled tracks your income, expenses, and mileage in real time and calculates your tax as you go. No more January panic. No more missed deadlines. Get started for free.

Quick Reference

DateActionPenalty if Missed
5 Oct 2025Register for SA (new users)Penalties and interest
31 Jan 2026File 2024/25 SA + pay tax£100 immediate + daily
31 Jul 20262nd payment on account5% surcharge + interest
31 Jan 2027File 2025/26 SA + pay tax£100 immediate + daily
31 Jul 20272nd payment on account5% surcharge + interest

Did you know? You can file your Self Assessment return as early as 6 April -- you do not have to wait until January. Filing early means you know exactly what you owe and have months to plan payment. HMRC will still not collect until the 31 January deadline.

Stay Ahead of Every Deadline

Fyled calculates your tax in real time so you always know what you owe. No January surprises, no missed deadlines, no penalties.

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