Tax Year Dates: When Each UK Tax Year Starts and Ends

Each UK tax year runs for 12 months from 6 April to 5 April, on dates set in law. The 2026/27 tax year covers 6 April 2026 to 5 April 2027, which is why it has two numbers. Your main deadlines for filing, paying and claiming refunds are worked out from these tax year dates.

Parliament, not HMRC, sets that 6 April start. The unusual date traces back to calendar reforms in 1752 and 1800, and it’s the reason the tax year finishes five days after the government’s financial year.

How you pay tax decides which tax year dates matter to you. If everything is deducted through PAYE from your pay or pension, your key tax dates fall after the year closes, once that year’s paperwork comes through.

Self Assessment brings its own registration, filing and payment dates, and you’ll have quarterly ones too if you’re signed up to Making Tax Digital. Overpaid? There’s a separate clock, and you normally have four years to claim it back.

This year’s tax year dates, month by month

These tax year dates repeat on the same day every year, but the weekday moves, which matters when you’re paying. Still to come for your 2025/26 return and the 2026/27 year:

• Saturday 31 October 2026: HMRC needs any paper 2025/26 return in by 11:59pm.
• Wednesday 30 December 2026: file online by now if you’d like what you owe taken through your tax code.
• Sunday 31 January 2027: the online 2025/26 return is due, and so is whatever you still owe for 2025/26, plus the first payment on account towards 2026/27 if you make them.
• Monday 5 April 2027: the tax year ends, and it’s normally the final day to reclaim tax overpaid in 2022/23.
• Tuesday 6 April 2027: 2027/28 begins, and your 2026/27 return can go in from this day.

After 2026/27 closes, these follow:

• Monday 31 May 2027: your employer’s deadline for handing you a P60, if you worked for them on 5 April 2027.
• Tuesday 6 July 2027: an employer that uses a P11D for your benefits must have given you a copy of the details.
• Saturday 31 July 2027: your second payment on account towards 2026/27 falls due.
• Tuesday 5 October 2027: the cut-off for telling HMRC you need to file for 2026/27, if you’re new to Self Assessment or didn’t have to file for 2025/26.
• Sunday 31 October 2027: paper 2026/27 returns are due.
• Thursday 30 December 2027: file online by now to pay a 2026/27 bill through your tax code.
• Monday 31 January 2028: the online 2026/27 return and its balancing payment are due, as is any first payment on account for 2027/28.

Both 31 January 2027 and 31 July 2027 fall at a weekend. Bacs and Direct Debit payments for those two deadlines need to land by the preceding Friday: 29 January and 30 July.

Paid through PAYE? Your key tax dates

When all your tax is taken through PAYE, the dates to watch come after each 5 April:

• Your employer has to hand you a P60 by 31 May if you were working for them on 5 April.
• If your employer reports your benefits in kind on a P11D, you’re due a copy of that information by 6 July, and benefits taxed through payroll aren’t reported on a P11D at all.
• From June to March after the year ends, HMRC sends a P800 or a Simple Assessment letter if your tax for the year came out too high or too low.

The letters are limited to people who are employed or receive a pension. For anyone registered for Self Assessment, HMRC corrects the bill automatically instead.

Tax owed on a P800 is usually recovered through your tax code, and HMRC usually splits it into equal monthly amounts over the 12 months from the next 6 April. This happens automatically if all three of these apply:

• You owe under £3,000.
• Your tax is paid through an employer or a pension provider.
• Your income above the Personal Allowance is high enough to cover what you owe.

If HMRC can’t collect it this way, it will write to you with other ways to pay. There’s more on the letter itself in the P800 form guide.

Tax weeks, tax months and week 53

Payroll runs to its own calendar within the tax year. A tax week is a run of seven days beginning 6 April, and a tax month starts on the 6th of one calendar month and ends on the 5th of the next, so the first tax month runs 6 April to 5 May.

A year of 365 or 366 days can’t be split evenly into weeks, so at least one day is left at the end. Those leftover days form week 53, which is 5 April in an ordinary year, or 4 and 5 April when 29 February falls inside the tax year.

If week 53 contains your weekly payday, that tax year brings 53 paydays rather than 52. Where tax is due on the extra one, your employer calculates it on a week 1 basis, without the running totals built up earlier in the year.

In some years, payrolls run fortnightly or every four weeks get an extra payday too, known as week 54 and week 56 respectively.

Online or paper sets your tax return deadline

The standard Self Assessment dates are fixed by the end of the tax year they relate to. For a tax year that ends on 5 April, the usual deadlines run as follows:

• 5 October: register with HMRC if you need to file and have never sent a return, or registered before but didn’t have to file for the year before.
• 31 October: a paper return must reach HMRC by 11:59pm.
• 30 December: to have a bill under £3,000 collected through your tax code, file online by this date, and HMRC only does this if you already pay tax through PAYE and the amount fits within its limits, which depend on your PAYE income and the tax you usually pay.
• 31 January: online returns are due by 11:59pm, and so is any balancing payment plus the first payment on account if you make them.
• 31 July: the second payment on account is due, if you make them.

A payment on account is half of the previous year’s tax bill, and for the self-employed that bill includes Class 4 National Insurance. The balancing payment also covers anything owed for capital gains, and for student loans if you’re self-employed.

Payments on account don’t apply if last year’s bill came to less than £1,000, or if over 80% of your tax was already collected outside Self Assessment, through your tax code for instance.

Registering late can lead to a penalty. Leave registration until after 5 October and HMRC will tell you your own filing deadline, 3 months on from the date of its letter or email. Any tax you owe is still due on 31 January.

There’s no need to hold off until January, since a return can be sent any time after 5 April. The exact dates for the latest year are listed under Self Assessment deadlines on GOV.UK.

Paying when a deadline falls on a weekend

Payment deadlines falling on a Saturday, Sunday or bank holiday effectively come early: the money has to be with HMRC by the working day before. The rule doesn’t apply to Faster Payments or to payments by debit or credit card.

How quickly your payment arrives depends on the method:

• Same or next day: Faster Payments, CHAPS, online payment by debit or corporate credit card, and paying in at your bank.
• 3 working days: Bacs, or a Direct Debit already set up with HMRC.
• 5 working days: a Direct Debit you’re setting up for the first time.

If 31 January or 31 July lands at a weekend, a Bacs payment must arrive by the Friday before, which means sending it at least three working days ahead of that Friday.

A deadline’s weekday changes every year, since tax year dates are fixed but the calendar isn’t. The full list of ways to pay a Self Assessment bill includes cheques and payment plans as well.

Quarterly updates under Making Tax Digital

If you’re within Making Tax Digital for Income Tax for self-employment or property income, you’ll also send HMRC an update every quarter from compatible software. Each update is due on the 7th of August, November, February or May, and covers the tax year up to that point.

A quarterly update is a summary rather than a tax return. You still file the year’s return by 31 January after it ends, and the year before you joined is filed in the normal way.

Whether you have to join depends on your qualifying income from an earlier tax year, with the threshold coming down in stages.

The guide to Making Tax Digital in 2026 sets out the thresholds and when each one applies.

Miss the tax return deadline and it’s £100

Miss the tax return deadline and HMRC charges an initial £100 penalty. Further charges are added the longer the return is late:

• 3 months late: £10 for each day, capped at £900.
• 6 months late: another £300 or 5% of the tax due, if that’s higher.
• 12 months late: a further £300 or 5%, again whichever is higher.

Late payment brings its own penalties: 5% of the tax still unpaid at 30 days, at 6 months and at 12 months. Interest is charged as well, and since 6 April 2025 HMRC’s late-payment rate for most taxes has been set at 4% above the Bank of England base rate.

HMRC’s interest rates are linked to the base rate, which is why the formula matters more than any single percentage. The penalties are explained in more detail on the Self Assessment penalties page on GOV.UK.

Refunds can normally be claimed for four years

You normally have until four years after a tax year ends to reclaim tax you overpaid in it. Each cut-off lands on 5 April, so every spring another year closes. Here’s how it works out for recent tax years:

An exception can apply where an HMRC error caused the overpayment.

The routes for claiming, from your personal tax account to the paper forms, are set out in the guide to how to claim your HMRC tax refund.

End of tax year planning works both ways

Some allowances belong to a single tax year and lapse when it ends. The ISA allowance works like this (£20,000 for 2026/27), and anything left unused can’t be carried forward.

Gift Aid works differently. You can put donations made after 5 April on the return for the year that’s just ended, provided you make them before sending it and the return isn’t late. Across the two years, your donations can’t exceed four times the income tax or Capital Gains Tax you paid in the earlier one.

Pensions can reach back as well. After using this year’s annual allowance, which is £60,000 for 2026/27, you may be able to use unused allowance from the previous 3 tax years, as long as you belonged to a registered pension scheme in each year you’re drawing from.

None of that unused allowance can be added to the money purchase annual allowance.

Put together, end of tax year planning has two halves: spend the old year’s allowances before 5 April, then check which rules still let you draw on earlier years once it has passed.

Why tax year dates run from 6 April

The tax year is defined in section 4 of the Income Tax Act 2007 as 6 April to the following 5 April. It also ties each year’s income tax to legislation: no Act of Parliament, no charge for that year.

In the Act a year is written as 2026-27, meaning the year beginning 6 April 2026, while HMRC guidance prefers 2026 to 2027. The two styles describe exactly the same period.

The date itself goes back to the calendar. England’s legal year used to start on 25 March (Lady Day), and the switch in 1752 removed 11 days, with 14 September following directly after 2 September.

According to the University of Nottingham’s Manuscripts and Special Collections team, those lost days moved the year’s start to 5 April, and one more skipped day in 1800 took it to 6 April.

Central government counts its finances over a different 12 months. The Interpretation Act 1978 has that financial year ending on 31 March, and Corporation Tax rates apply to each financial year beginning 1 April.

Since 2024/25, sole traders and partners have been taxed on the profit arising in the tax year itself, with special rules for accounting dates from 31 March to 5 April.

Get ready for your next tax year dates

Because the law fixes tax year dates, you can plan the same checks every year. If PAYE is your only tax route, look for a P60 by 31 May and, from June to March, any P800 or Simple Assessment letter.

If you’re in Self Assessment, plan backwards from 31 January, and from 31 July too if you make payments on account. Check which weekday each deadline falls on before you pick a payment method.

Before 5 April, use any allowances that belong to the year that’s ending, and note the refund cut-off for the year about to drop out of reach.

Not sure whether you need to file at all? The guide to what a Self Assessment tax return is covers who needs one.

Tax Year Dates: Key Takeaways

• Under section 4 of the Income Tax Act 2007, the UK tax year covers the 12 months from 6 April to the next 5 April, and each year is named after both calendar years it spans.
• The standard Self Assessment deadlines are 31 January for an online return, which is also the payment date, and 31 October for a paper one.
• PAYE taxpayers can expect a P60 by 31 May, and any P800 or Simple Assessment letter arrives between June and March.
• A payment deadline on a weekend or bank holiday moves your cut-off back to the last working day before it, unless you pay with Faster Payments or a debit or credit card.
• Late returns attract a £100 penalty straight away, and late payments add 5% penalties plus interest at 4% above base rate.
• Overpaid tax can normally be reclaimed for four years after the tax year ends, with each year’s window closing on 5 April.