Tax Deadline Tracker

Use the tax deadline tracker

Set your filing situation in the tool above and it will list the UK tax deadlines that apply to you, count down the days to each one, and let you export them to your calendar. Below, you will find what each date means, who it affects, and the costs of getting it wrong.

The UK tax deadlines that matter most in 2026/27

The tax year runs from 6 April 2026 to 5 April 2027. Most personal-tax deadlines hang off that calendar. These are the dates a self assessment deadline tracker should always show you:

Two of these dominate everything else: 31 January (online filing plus tax owed) and 31 July (the second payment on account). If you only set two reminders, set those.

How the tax deadline tracker works

The maths behind the countdown is simple, but the logic of which dates apply to you is where it earns its keep. In plain terms:

Days remaining = deadline date − today's date.

The tracker takes each relevant statutory deadline, subtracts today, and shows you the gap. A red or urgent state usually means a deadline is inside the next 30 days. The tool then builds a calendar file (an .ics event) so you can drop the date into Google Calendar, Outlook or Apple Calendar with an alert a week or two before.

Working out which deadlines apply depends on your profile. A PAYE employee with no side income normally has nothing to file at all. A sole trader or landlord with untaxed income usually needs to register by 5 October after the tax year ends, then file online by the following 31 January. A VAT-registered business has quarterly VAT return and payment dates instead, now filed through Making Tax Digital-compatible software. If you are not sure whether you even need to file, the do I need to file a tax return checker settles it in under a minute.

Worked example: a freelancer's tax-year timeline

Imagine Priya, a freelance designer who went self-employed in June 2026. Here is how the key deadlines land for her first full year, and why each one matters:

• 5 October 2027: Priya must register for Self Assessment for the 2026/27 tax year. Miss this and HMRC can charge a failure-to-notify penalty based on the tax due.
• 31 January 2028: She files her 2026/27 online return and pays the tax owed. Say her taxable profit works out so that her income tax plus Class 4 National Insurance comes to £5,000. That £5,000 is due in full on this date.
• Payments on account kick in: Because her bill is over £1,000, HMRC also asks for payments on account towards the next year. Each one is half of this year's bill, so 50% × £5,000 = £2,500. The first £2,500 is due on 31 January 2028 alongside the £5,000 - a £7,500 total - and the second £2,500 on 31 July 2028.

That 31 January total of £7,500 is the moment most new freelancers get caught out: they budgeted for £5,000 and forgot the first payment on account. You can model the exact split with the payments on account calculator, and estimate the bill itself with the Self Assessment tax calculator.

Payments on account: the deadline that catches people out

Payments on account are advance instalments towards your next tax bill. You make them if your last Self Assessment bill was more than £1,000 and less than 80% of your tax was collected at source (for example through PAYE). Each instalment is half of your previous year's bill, paid on 31 January and 31 July. When you finally file, any shortfall or refund is settled as a balancing payment on the following 31 January.

If your income has dropped, you can apply to reduce your payments on account - but if you reduce them too far and end up owing more, HMRC charges interest on the difference. Treat the 31 July date as seriously as 31 January; it is easy to forget a payment with no return attached to it.

Capital gains and the 60-day clock

Some deadlines do not wait for 31 January. If you sell UK residential property (a buy-to-let or second home, not normally your main home) at a gain, you must report it and pay the Capital Gains Tax within 60 days of completion through a separate online CGT return. For 2026/27 the CGT rates on residential property are 18% within your remaining basic-rate band and 24% above it, after the £3,000 annual exempt amount. Work out the figure first with the 60-day CGT reporting calculator or the broader capital gains tax calculator, then diarise day 60 from completion - it is one of the easiest deadlines to miss because it is not tied to the tax-year calendar.

What missing a deadline costs you

Late Self Assessment filing triggers an automatic fixed penalty even if you owe no tax, followed by further daily and percentage-based penalties the longer you leave it, plus interest on any tax paid late. The amounts escalate quickly, so filing a nil or estimated return on time is almost always better than filing nothing. You can see how the charges build up using the Self Assessment penalty calculator. For the official rules and current penalty amounts, check the gov.uk guidance at gov.uk/self-assessment-tax-returns/deadlines.

Regional and situational notes

Deadline dates are the same across the whole UK - 6 April, 31 July, 5 October, 31 October and 31 January apply in England, Wales, Scotland and Northern Ireland alike. What differs is the tax you calculate, not when you file it. Scottish taxpayers pay Scottish income tax rates and bands on their non-savings income, but still file the same UK Self Assessment return by the same 31 January deadline. Property tax also varies by nation (SDLT in England and Northern Ireland, LBTT in Scotland, LTT in Wales), each with its own short filing-and-payment window after completion, usually handled by your solicitor. MoneyHelper has a plain-English overview of Self Assessment timing at moneyhelper.org.uk.

Common mistakes to avoid

• Forgetting the first payment on account. Budgeting only for the balancing payment and being blindsided by the extra 50% on 31 January.
• Leaving registration too late. The 5 October registration deadline comes months before you file; miss it and you may face a failure-to-notify penalty.
• Confusing the paper and online deadlines. Paper returns are due 31 October; online returns get three more months to 31 January.
• Assuming PAYE means nothing to file. Side income, rental profit, dividends over the £500 allowance or income over £100,000 can all pull you into Self Assessment.
• Missing the 60-day CGT window. Property gains have their own clock that runs from completion, not from the tax-year end.
• Paying late even after filing on time. Filing and paying are separate; interest runs from the day the tax was due.

The single best habit is to set calendar alerts a fortnight before each date, then check the tracker monthly so nothing surprises you. Employers should also note the P60 deadline and the P11D deadline for reporting benefits in kind.

These dates and figures are estimates for guidance only and not personal tax or financial advice. Always confirm your own deadlines with HMRC or a qualified adviser.

Related tax tools

Plan the whole year with the Self Assessment tax calculator, model your instalments with the payments on account calculator, and check the cost of slipping a date with the Self Assessment penalty calculator.