UK tax and accounts basics, explained
Self Assessment Payments on Account Explained
8 November 2026
General information, not tax adviceEvery figure here is quoted from GOV.UK, with the tax year it applies to. Your own position can differ, so check your HMRC online account and the linked GOV.UK page, or speak to a qualified accountant.
Payments on account often surprise people in their first or second year of Self Assessment. This guide explains what they are, when they're due and how they're worked out, using GOV.UK's own wording and examples. It's general information, not tax advice.
Quick answer: GOV.UK says payments on account are payments towards your next tax bill, including Class 4 National Insurance if you're self-employed. Each one is usually half of the tax you owed the previous year, and they're due by midnight on 31 January and 31 July. You don't have to make them if last year's tax bill was less than £1,000, or if you paid more than 80% of it outside Self Assessment.
Key Takeaways
Payments on account are 2 instalments towards your next Self Assessment bill.
Each one is usually half of the tax you owed the previous year.
They're due by midnight on 31 January and 31 July.
If they don't cover your bill, you make a balancing payment by 31 January the following year.
You can ask HMRC to reduce them if you know your tax will be lower than last year.
What payments on account are
GOV.UK's page on payments on account describes them as payments towards your next tax bill, including Class 4 National Insurance if you're self-employed. They help spread the cost of your tax by making payments in 2 instalments. Each payment is half of the tax you owed last year.
They're due by midnight on 31 January and 31 July. GOV.UK's Self Assessment deadlines page also calls 31 July the second payment deadline if you make payments on account.
Who has to make them
GOV.UK says you must make the 2 payments unless either:
the amount of tax you owed last year was less than £1,000
last year you paid more than 80% of the tax you owed outside Self Assessment, for example through your tax code or because your bank had already deducted interest on your savings
Your Self Assessment statement or online account will show how much they are, if you need to pay them.
How they're worked out
GOV.UK says payments on account are based on your estimated earnings, usually the amount you earned the previous year. If you earn more than estimated, you may still have tax to pay on top. This is known as a balancing payment. If you earn less than estimated, you may be able to claim a tax refund.
The balancing payment is worked out by taking the payments on account you've made away from the total tax you owe. You must pay it by midnight on 31 January the following year.
GOV.UK's example, if you made payments on account last year
GOV.UK gives this example. Your bill for the 2023 to 2024 tax year is £3,000. Based on your 2022 to 2023 earnings, you made 2 payments on account of £900 each (£1,800 in total) on 31 January 2024 and 31 July 2024.
Payment | Amount | Due |
|---|---|---|
Balancing payment for 2023 to 2024 (£3,000 minus £1,800) | £1,200 | 31 January 2025 |
First payment on account towards 2024 to 2025 (half of £3,000) | £1,500 | 31 January 2025 |
Second payment on account towards 2024 to 2025 | £1,500 | 31 July 2025 |
That means you'll have paid £2,700 by 31 January 2025. If your 2024 to 2025 bill turns out to be more than £3,000, you make a balancing payment by 31 January 2026.
GOV.UK's example, if it's your first year
If you didn't make any payments on account last year, for example because it's your first time filing Self Assessment, GOV.UK says you pay both the full amount of your tax calculation and your first payment on account towards your next bill.
In GOV.UK's example, a £3,000 bill for 2023 to 2024 means £4,500 is due by midnight on 31 January 2025: the £3,000 bill plus a first payment on account of £1,500. A second payment on account of £1,500 follows on 31 July 2025. This is why the first January can feel larger than expected. If you've just started out, our guide on how to register as self-employed in the UK covers the earlier steps.
Checking and reducing your payments on account
GOV.UK says you can check payments on account you've made, and those still due, by signing in to your online account and selecting View statements. If you filed a paper return, your last Self Assessment statement shows them.
If you know the tax you owe will be lower than last year, you can ask HMRC to reduce your payments on account, online or by post using form SA303. You'll need to include the amount you expect to make. GOV.UK warns that if you reduce them and your bill turns out higher than expected, you'll be charged interest on the difference.
Where payments on account fit in the year
Payments on account sit alongside the main Self Assessment dates. Our guide to Self Assessment tax return deadlines lists the filing and payment deadlines for the 2025 to 2026 tax year.
Your bill depends on your profit, so allowable expenses matter too. Our guide to allowable expenses for the self-employed sets out what GOV.UK says you can claim.
If you use Making Tax Digital for Income Tax, GOV.UK's Understand your Self Assessment tax bill guide says you must pay any amount listed as due in either your Self Assessment account or your Making Tax Digital for Income Tax account.
Our guide to Making Tax Digital for Income Tax explains who needs it.
For the main dates in one place, see key tax dates and thresholds.
Frequently asked questions
When are Self Assessment payments on account due?
GOV.UK says they're due by midnight on 31 January and 31 July.
How much is each payment on account?
GOV.UK says each payment is usually half of the tax you owed the previous year.
Do I have to make payments on account?
Not always. GOV.UK says you don't have to if the tax you owed last year was less than £1,000, or if last year you paid more than 80% of the tax you owed outside Self Assessment.
Can I reduce my payments on account?
Yes. GOV.UK says you can ask HMRC to reduce them online or by post with form SA303 if you know your tax will be lower than last year. If your bill turns out higher, you'll be charged interest on the difference.