Two different HMRC letters are behind this week’s headlines, and it is easy to mix them up. One tells 700,000 people they are owed money. The other tells savers and pensioners they owe tax. If you have had a letter — or seen “£473” trending — here is which is which, and what to do about a genuine tax bill.
The £473 story: a refund, not a bill
The figure making headlines is a P800 Tax Calculation, the letter HMRC sends when it works out you have overpaid or underpaid tax through PAYE. HMRC has told the press that around 700,000 people who were sent P800 letters over summer 2026 are still owed a refund, averaging £473, and has urged them to claim it — either online through GOV.UK, in the HMRC app, or through your Personal Tax Account. If your letter says you can claim online, the money typically arrives within 5 working days; if it says a cheque is on its way, that takes around 6 weeks and needs no action from you.
If your letter is a P800 and it says you owe money instead, that is also collected differently from a Simple Assessment — usually through an adjustment to next year’s tax code, unless the amount is too large for a code to absorb.
What a Simple Assessment (PA302) actually is
A Simple Assessment, sent as a letter still commonly referred to as a PA302, is HMRC’s own calculation of tax you owe that it cannot collect automatically through PAYE or Self Assessment. GOV.UK describes it as setting out “how much tax you owe, how it was calculated and how to pay.” You do not need to do anything to trigger one — HMRC issues it directly using data it already holds from employers, pension providers and, for savings, your bank or building society.
Typical triggers include:
- Interest on savings or dividends above your tax-free allowances
- A second source of untaxed income
- Pension income that pushes you over your Personal Allowance
- Tax owed that is too large to collect through a tax code (broadly, £3,000 or more)
This is different from Self Assessment, where you calculate and report the tax yourself on a return. A Simple Assessment is HMRC doing the sum for you and sending you the result.
Why savers and pensioners are getting them right now
HMRC is issuing roughly 1.8 million Simple Assessment letters for the 2025-26 tax year (6 April 2025 to 5 April 2026). Working-age customers started receiving theirs from 30 June 2026; pensioners started from 12 August 2026. A second tranche, covering Bank and Building Society Interest (BBSI) data reported later, goes out between October and December 2026 — so a letter about savings interest can arrive well after the tax year has ended.
The underlying reason more people are getting one is structural, not a one-off event: the standard Personal Allowance has been held at £12,570 since 2021 and stays there through 2030-31 (Autumn Budget 2025 extended the freeze a further three years beyond its original April 2028 end date), while savings rates have been higher in recent years than for most of the previous decade. State Pension alone can use up most of a pensioner’s Personal Allowance, leaving little of it — and potentially little of the £5,000 starting rate for savings — to cover interest before the Personal Savings Allowance (£1,000 basic rate, £500 higher rate, £0 additional rate) takes over. For the full mechanics of how those three allowances stack for pension and savings income, see tax on savings interest for pensioners.
How to check the calculation
Before paying anything, check what HMRC used to work out the bill. Check your Simple Assessment tax bill online to see:
- Why HMRC sent it
- How the tax was worked out, step by step
- What income, savings interest or benefits were included
Compare the interest figure against your own bank and building society statements or interest certificates — banks report annual interest to HMRC after the tax year ends, and it is a live data feed, not something you submit yourself, so errors can occur if an account was closed, jointly held, or held with a provider that reported late. Use the tax on savings interest calculator to re-run the numbers yourself: enter your income and interest and it applies the same Personal Allowance, starting rate for savings and Personal Savings Allowance HMRC should be using.
If you receive more than one Simple Assessment for the same year, only the most recent matters — it shows your total liability, and you pay the difference from anything already paid, not each letter separately.
How and when to pay
The deadline depends on when the letter arrives:
- Letter received before 31 October 2026 (for the 2025-26 tax year): pay by 31 January 2027.
- Letter received on or after 31 October 2026: pay within 3 months of the date on the letter.
You will need the 14-character payment reference on the letter, which starts with the letter X. You can pay in full or in instalments, provided the total amount clears by the deadline. If you cannot pay on time, HMRC’s Time to Pay service lets you estimate a monthly instalment plan rather than missing the deadline outright, which can trigger late-payment interest and penalties.
If you disagree with the amount
Contact HMRC within 60 days of the date on the letter if you think any of the figures are wrong — for example, interest counted twice, income from a closed account, or a benefit that should not be included. GOV.UK is explicit that if the figures turn out to be correct, you still need to pay by the original deadline while the query is being looked at, so raise a dispute promptly rather than simply not paying.
Quick checklist
- Work out which letter you have — a P800 (refund or PAYE adjustment) or a Simple Assessment/PA302 (a standalone tax bill).
- If it is a Simple Assessment, check the income and interest figures against your own records.
- Re-run the savings-interest maths with the tax on savings interest calculator if pension or interest income is involved.
- Note the deadline from the letter — usually 31 January 2027 for 2025-26 letters issued before 31 October 2026.
- Contact HMRC within 60 days if something looks wrong; otherwise pay by the deadline using the reference starting with X.