Answers · UK 2025/26

What is the 31 July payment on account deadline for Self Assessment?

31 July is the deadline for the second Self Assessment payment on account for the previous tax year, an advance payment towards your current-year tax bill based on half your prior year's liability. Missing it triggers interest from 1 August, though (unlike the 31 January deadline) there is no automatic late-filing penalty since no return is due.

Last updated: 1 July 2026Last reviewed: 1 July 2026How we verify

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If you are self-employed or otherwise file Self Assessment and your tax bill was over £1,000 last year (with less than 80% collected at source), HMRC usually requires two "payments on account" during the year, each normally half of your previous year's tax bill: the first due 31 January, the second due 31 July. **What the 31 July payment actually is** The 31 July payment on account is the second of two advance instalments towards your CURRENT tax year's bill (for most people filing now, this is the payment on account for 2025/26, due before the 2025/26 return itself is even filed). It is not a new tax charge -- it is a prepayment based on the assumption that your income this year will be similar to last year. **What happens if you miss it** HMRC charges interest (not a fixed penalty) on late payments on account, running from 1 August at HMRC's official late payment interest rate, compounding daily until paid. Unlike the 31 January Self Assessment deadline, there is no £100 automatic penalty for missing 31 July specifically, because no tax return is due on that date -- but the interest still adds up and HMRC will eventually chase the debt, and persistent non-payment can escalate to debt collection action. **Reducing the payment if your income has dropped** If you know your current-year income and tax liability will be lower than last year (for example your self-employed profits have fallen, or you have stopped a source of income), you can apply to HMRC to reduce your payments on account, either online via your personal tax account or by post using form SA303. Be careful: if you reduce the payment too far and your actual liability turns out higher, HMRC charges interest on the shortfall as if you had underpaid, so only reduce it based on a realistic, well-evidenced forecast. **Worked example** Amir's 2024/25 Self Assessment bill was £6,000. HMRC set two payments on account of £3,000 each for 2025/26: due 31 January 2026 and 31 July 2026. If his actual 2025/26 profits are similar, the two payments on account (£6,000 total) cover his 2025/26 liability, and any small balancing amount or refund is settled when he files his 2025/26 return by 31 January 2027. If his profits fell significantly in 2025/26, he could have applied to reduce the July payment in advance rather than overpaying and waiting for a refund. **Practical tip** Set a reminder well before 31 July each year, and if cash flow is tight, contact HMRC proactively about a Time to Pay arrangement rather than simply missing the deadline -- proactively agreed payment plans generally avoid more serious enforcement action.