HMRC letters • Plain English

Payment on account and January payment reminders

A reminder is HMRC nudging you to pay by 31 January. HMRC may send a "January payment reminder" if your return has been received but not processed, so the amount due is not yet known. A payment on account is a half-year instalment towards next year's bill, due 31 January and 31 July.

By The HandySums teamLast checked:

Who gets this

Anyone in Self Assessment, especially in December and June.

How to recognise it

  • It looks like a statement with a payslip, but has no accounting figures.
  • It is sent around December if you have not filed, or if your return has been received but not processed.
  • Your online account or statement shows your payments on account and what you owe.

What to do

  1. Sign in to your online account and open the latest return, then "View statements" to see what is due.
  2. Make both payments on account unless last year's tax bill was under £1,000, or you paid more than 80% of it outside Self Assessment (for example through your tax code).
  3. If you know this year's tax will be lower, ask HMRC to reduce your payments on account online or on form SA303. If you reduce too far you pay interest on the difference.

By when

31 January and 31 July, midnight.

What happens if you ignore it

  • Late payment penalties of 5% at 30 days, 6 months and 12 months, plus interest.

Official GOV.UK pages

The reminder form names (SA309A and SA309C) come from HMRC's internal Self Assessment manual, which dates from the paper-statement era. Letters may be labelled differently today.

Not sure it is genuine?

Do not use any link or phone number printed in a message you are unsure about. Check the list of genuine HMRC letters, then find HMRC’s contact details on GOV.UK yourself. You never need to upload your letter to HandySums, and we would never ask.

CalculatorPayments on account calculatorYour 31 January and 31 July payments, the balancing payment, and whether CIS means you owe none.GuidePayments on account guideWhy January can be 1.5 times your bill, the £1,000 and 80% rules, and how CIS affects them.DatesHMRC dates and calendarEvery HMRC deadline that matters to the self-employed, with a calendar file.

Sources and review

Last checked: 1 November 2026. What this letter is, the deadlines and the penalties described on this page. Written and checked by the HandySums team against the GOV.UK pages below. HandySums is independent and not an accountancy firm — see how we check our sums.

A guide, not tax advice. Results and explanations are a guide and HMRC has the final say. Always follow the dates and instructions on your own letter, and check with HMRC or a qualified accountant if unsure.