HMRC Simple Assessment letter: what it means and what to do
Updated: 2026-10-18
A Simple Assessment is a tax bill from HMRC for an earlier tax year. Check it, pay by the date on the letter, and if something is wrong contact HMRC within 60 days.
What is this letter?
HMRC sends a Simple Assessment (also called a PA302) when you owe tax that could not be collected through your tax code. GOV.UK gives these examples: you owe Income Tax that cannot be collected through your tax code, you owe £3,000 or more, you must pay tax on your State Pension, or you have untaxed income such as savings interest or dividends.
It is not the same as a Self Assessment tax return. You get it by post or in your Personal Tax Account. It shows how much tax you owe, how it was worked out and how to pay. You can check it on GOV.UK. If you get more than one for a year, the latest shows the total for that year.
How much time do I have?
| Event | Counted from | How long | Source |
|---|---|---|---|
| Pay: letter dated before 31 October 2026 (tax year 2025-26) | Letter date | By 31 January 2027 | GOV.UK |
| Pay: letter dated on or after 31 October 2026 | Letter date | Within 3 months of the date of the letter | GOV.UK |
| Tell HMRC something is wrong | See your letter (we assume the date of the letter) | Within 60 days | GOV.UK |
| Pay or call if you cannot pay (letter IDMS99P) | Date of the letter | 28 days, according to HMRC's letter checker page. Follow the date on your letter. | GOV.UK |
| Payment sent with wrong reference | Date you paid | Contact Income Tax enquiries to ask to move it | GOV.UK |
The two pages on GOV.UK show different timings. The Simple Assessment page gives 31 January 2027 or 3 months. The letter checker page says 28 days to pay or call. Always follow the deadline printed on your letter, and ask HMRC if it is unclear.
What do I do, step by step?
- Check the letter with HMRC's list on GOV.UK. See our guide "Is this HMRC letter real? 7 checks".
- Find the deadline on your letter and write it in your calendar.
- Check the bill at gov.uk/check-simple-assessment. See which income, savings interest or benefits were included.
- Compare it with your own papers: payslips, P60, pension statements, bank interest.
- If something is wrong, contact HMRC within 60 days.
- If it is right, pay in full or in smaller instalments. The full amount must be paid by the deadline. Use the 14-character payment reference that starts with X.
- Pay online, by bank transfer or by cheque. Keep proof.
- If you cannot pay on time, ask for help. Use gov.uk/difficulties-paying-hmrc/overview or call 0300 322 7835 (number on the letter checker page).
What letter should I send? (Ready-made letter)
You may need a letter to HMRC to say which figure is wrong and why, to ask for a time-to-pay arrangement, or to ask for a payment to be moved to the right bill. UK Help Agent can write it in English from your voice message or a photo of the letter.
Record what happened, or send a photo of the letter. The explanation is free. A ready letter is £4.
What if the deadline has passed?
If the deadline has passed, contact HMRC now. Do not ignore the letter. Tell them you want to pay or agree a plan. GOV.UK points to its "difficulties paying HMRC" page for help. If you paid too much, contact HMRC for a refund. If you paid with a wrong reference, the payment may be delayed or applied to another bill, so ask HMRC to move it. We could not confirm the penalties on the pages we read, so check gov.uk.
Is it the same in England, Scotland, Wales and Northern Ireland?
HMRC is UK-wide. The pages we read do not mention Scotland, Wales or Northern Ireland separately. Scottish Income Tax rates are different, but we did not confirm how that affects a Simple Assessment, so check gov.uk if you live in Scotland.
Frequently asked questions
What is a PA302?
It is another name for a Simple Assessment, an HMRC tax bill for a previous tax year.
Who gets a Simple Assessment?
People who owe tax that cannot be collected through the tax code, owe £3,000 or more, pay tax on State Pension, or have untaxed income such as savings interest or dividends.
When must I pay?
Letters dated before 31 October 2026: by 31 January 2027. Letters dated on or after 31 October 2026: within 3 months of the letter date. Follow your letter.
What if the bill is wrong?
Contact HMRC within 60 days.
Can I pay in instalments?
Yes, but the full amount must be paid by the deadline on your letter.
Sources
- GOV.UK: Simple Assessment
- GOV.UK: Check your Simple Assessment
- GOV.UK: Check if a letter from HMRC is genuine
- LITRG: Is your HMRC letter genuine?
Checked on: 2026-10-17
This is general information, not legal advice. Rules can change. For your own case, check the sources above or ask a free adviser, for example Citizens Advice.