How to Pay Your Self Assessment Tax Bill: Methods and Deadlines
Understanding your Self Assessment payments
If you are self-employed, a landlord or receive other untaxed income, you settle your tax through Self Assessment. Knowing when and how to pay is just as important as filing the return itself — miss a deadline and HMRC will add interest, and in most cases a penalty too.
This guide explains the key deadlines, how payments on account work, the ways you can pay HMRC, and what happens if your payment is late. First-time filers must register and obtain a Unique Taxpayer Reference before they can pay — see the linked guide below.
Key payment deadlines
Two dates matter each year:
31 January — the balancing payment for the previous tax year, plus your first payment on account for the current year.
31 July — your second payment on account.
Payment is due by 11:59pm on the deadline, and the date does not shift if it falls on a weekend. Allow enough time for your chosen method to clear.
How payments on account work
Payments on account are advance instalments towards your next tax bill. Each instalment is half of your previous year's bill and covers income tax and Class 4 National Insurance — but not Capital Gains Tax.
For example, if your tax for the year comes to £4,000, you pay that £4,000 by 31 January along with a first payment on account of £2,000. A second £2,000 follows by 31 July. If next year's actual bill is higher, you settle the difference as a balancing payment the following January.
If your income falls, you can ask HMRC to reduce your payments on account. Be careful: reduce them too far and HMRC charges interest on any shortfall.
Ways to pay your tax bill
HMRC accepts several methods, and each takes a different time to arrive — so check before the deadline:
Faster Payments (online or telephone banking) — usually same or next day.
Debit card online — same or next working day.
Direct Debit — allow up to five working days the first time you set one up.
HMRC app — quick and secure.
Cheque by post — allow at least three working days.
You cannot pay with a personal credit card. Always quote your Unique Taxpayer Reference (UTR) followed by the letter "K", so HMRC allocates the payment correctly.
What happens if you pay late
Paying late triggers two separate charges: interest and penalties. These are on top of any late filing penalty, which is a separate charge for sending your return in late.
Interest is charged daily from the day after the deadline until the bill is cleared. On top of that, late payment penalties apply to the tax still outstanding:
5% after 30 days;
a further 5% after 6 months;
another 5% after 12 months.
If you cannot pay in full, you may be able to arrange a Time to Pay plan and spread the cost over monthly instalments. For debts up to £30,000 this can usually be set up online without contacting HMRC directly. Interest still applies, but acting early keeps the cost down and avoids enforcement action.
New to Self Assessment? Read our step-by-step guide to registering as a sole trader.
FAQ:
When is my Self Assessment tax due?
There are two dates: 31 January for the balancing payment and your first payment on account, and 31 July for the second payment on account. Both fall at 11:59pm.
What is a payment on account?
It is an advance instalment towards your next tax bill, equal to half of your previous year's bill. It covers income tax and Class 4 National Insurance.
Do I always have to make payments on account?
No. They do not apply if your last bill was under £1,000, or if at least 80% of your tax was collected at source, for example through PAYE.
What happens if I pay my tax bill late?
HMRC charges daily interest from the day after the deadline, plus penalties of 5% of the unpaid tax at 30 days, 6 months and 12 months.
Can I pay my Self Assessment bill in instalments?
Yes. You can pay in advance through a Budget Payment Plan, or set up a Time to Pay arrangement if you are struggling. Debts up to £30,000 can often be arranged online.
