What happens if I pay my payment on account late?

Unlike the 31 January balancing payment, a late payment on account does not trigger an automatic late-payment penalty — but interest runs from 1 August until you pay. If it is still unpaid by the next 31 January it rolls into your balancing payment, which can then attract penalties.

Deadlines · 5 min read · 20 July 2026

Do you owe a tax payment on 31 July?

Q: Do I have to pay tax on 31 July?

Only if HMRC has set up payments on account for you. That happens when 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). If so, your second payment on account is due by 31 July.

Q: How much is the second payment on account?

Each payment on account is usually half of your previous year's tax bill, so the 31 July payment is normally the same amount you paid on 31 January.

Q: Can I reduce my payment on account?

Yes. If you expect to earn less this year you can reduce your payments on account through your HMRC online account or by submitting form SA303. Don't over-reduce, though: if you underpay, HMRC charges interest on the shortfall.

If you're in Self Assessment, 31 July is the deadline a lot of people forget — the second payment on account. Here's who has to pay it, how much, and exactly what to do if the timing's tight this year.

The date: your second payment on account for the 2025/26 tax year is due by midnight on 31 July 2026.

What is the 31 July payment?

It's an advance instalment towards your next tax bill. HMRC asks most people in Self Assessment to pay their tax in two chunks — one on 31 January, one on 31 July — rather than all at once. Each chunk is called a payment on account. So the 31 July payment isn't a new or extra bill; it's the second half of tax you're paying ahead of time. (If you've ever wondered why your first January bill felt double, this is why.)

Do you actually have to pay it?

You'll only have a payment on account to make if both of these were true last year:

your Self Assessment tax bill was more than £1,000, and
less than 80% of your tax was already collected at source — for example through a PAYE job.

If HMRC set payments on account for you, the amount will have shown on your 31 January statement — and it's sitting in your HMRC online account now. If your last bill was under £1,000, or nearly all your tax comes out of a salary, you almost certainly have nothing due on 31 July.

How much is it?

Each payment on account is usually half of your previous year's tax bill. So the payment due on 31 July is normally the same amount you paid back on 31 January — no need to work anything out. Then any remaining difference is settled in a final "balancing payment" the following 31 January.

Not sure of the figure? It's on your HMRC account, or we can check it for you. Want to understand the whole cycle first? Our how-much-tax guide shows how the bill is built.

Your income has dropped? You can reduce it

Payments on account are based on last year — so if you expect to earn less this year, you could be paying too much up front. You can reduce your payments on account through your HMRC online account, or by submitting form SA303.

One word of caution: don't over-reduce. If you cut the payment and it turns out you owed more, HMRC charges interest on the shortfall back to the original date. It's worth getting the estimate right — which is exactly the sort of judgement call we make for clients.

What if you can't pay by 31 July?

Here's a bit of relief most people don't realise: a late payment on account is treated more gently than a late January bill.

No automatic penalty. Unlike the 31 January balancing payment, a late payment on account isn't hit with HMRC's automatic late-payment penalties.
But interest runs from 1 August. Interest is charged on whatever's unpaid, day by day, until you clear it — so it's still worth paying as soon as you can. (Check the current rate on GOV.UK.)
Don't let it drift to January. If a payment on account is still unpaid by the next 31 January, it rolls into your balancing payment — which can then attract late-payment penalties.

If money's genuinely tight, don't ignore it — you can set up a Time to Pay arrangement with HMRC to spread it over instalments. We can help you sort that out.

How to pay

Pay through your HMRC online account by bank transfer, debit card, or your banking app — and give it a few working days to land before the 31 July deadline. Quote your UTR as the reference so it's matched to the right account.

Never want to think about a tax deadline again?

We track the dates, tell you the figure in advance, and file it all for you — from £25 a month.

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Common questions

Do I have to pay tax on 31 July? Only if HMRC has set up payments on account for you — which happens when your last bill was over £1,000 and under 80% of your tax was collected at source.

How much is the second payment on account? Usually half your previous year's tax bill — the same as you paid on 31 January.

What if I pay late? No automatic penalty on a payment on account, but interest runs from 1 August. Leave it unpaid past the next 31 January and it can then be penalised.

Related guides

Payments on account explained — why the first bill feels double
Self Assessment deadlines — every date that matters
Missed a tax deadline? — what happens next
Help with your tax return — if you'd rather hand it over

This guide is general information, not personal tax advice. Rules, rates and interest can change — always confirm the current position on GOV.UK or ask us to check your situation.

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