PAYE tax refunds: what a P800 letter means and how to claim without a middleman

Why job changes, emergency codes and leaving work mid-year lead to overpaid tax, and how to get it back for free

PAYE is designed to take the right tax over a full year, spread evenly. When your year is not even, because you changed jobs, stopped work, had a gap or were put on an emergency code, it often takes too much. HMRC checks after the year ends and writes to people it thinks have overpaid. Those letters are landing now for 2025/26. This guide explains what to look for and how to get the money without paying anyone a cut.

Key points: a P800 is HMRC's calculation, not a bill or a scam. Claim online through the HMRC app and the refund reaches your bank in about five working days. Do nothing and a cheque follows, which takes longer. You can claim back to 2022/23. HMRC never sends refund links by text or email.

When PAYE takes too much

Your Personal Allowance of £12,570 is spread across the year, £1,047.50 a month. Each payslip assumes you will earn at the same rate for all twelve months. That assumption breaks when:

You start a new job and go on an emergency code, so the allowance is not carried forward properly.
You have two jobs and one is taxed at BR with no allowance, while the other does not use the whole allowance.
You leave a job part way through the year and do not work again, so months of allowance go unused.
You retire, take maternity leave, become a student or go abroad.
You receive a redundancy payment or bonus that pushes a single month into a higher band.
You take a pension lump sum, which is taxed on the emergency basis and nearly always over-taxed.

What a P800 is

After 5 April HMRC reconciles the pay and tax reported by every employer and pension provider. Where the totals do not match what you should have paid, it sends a P800 tax calculation. Most go out between June and November.

The letter shows your total income, allowances, tax due and tax paid, and the difference. It says either that you are due a refund or that you owe tax. Check the figures against your P60 and P45s before accepting them. HMRC's income figures come from employers and are usually right, but allowances and benefits can be wrong.

If you file a self-assessment return you will not get a P800. Any overpayment comes through the return.

How to claim the refund

Log in to the HMRC app or your personal tax account at gov.uk.
Find the refund under "Your tax" or in the message about your P800.
Enter your bank details. The payment usually arrives within five working days.

If you do not claim online within the period stated on the letter, HMRC posts a cheque. That can take several weeks and needs paying in.

If you think you overpaid but no P800 has arrived by the end of November, you can ask HMRC to check. Use the app, the online form or the phone line, with your National Insurance number, employer details and P45 or P60 to hand. Claims can go back four years, so 2022/23 remains open until 5 April 2027.

Mid-year claims

You do not always have to wait for the year to end.

Stopped working and will not work again this tax year. Use form P50 after four weeks without pay, or after eight weeks if you are claiming Jobseeker's Allowance.
Took a pension lump sum and were over-taxed. Use P53 or P55 depending on whether you emptied the pot, and the refund comes within about 30 days.
On an emergency code in a continuing job. Fix the code through the app and the overpayment comes back through your next payslip.

Scam warnings

Refund scams peak in the months P800s go out. HMRC does not send emails, texts or WhatsApp messages with links to claim a refund. It does not ask for card details to release a payment.

Genuine contact comes by letter or as a message inside the app or your tax account. If in doubt, close the message and log in directly by typing the gov.uk address. Report suspicious messages by forwarding them to HMRC's phishing team.

Refund companies are a separate problem. They fill in the same free form for you and keep a slice, often a third or more, and some sign clients up to recurring agreements. If you have authorised one and want out, tell HMRC in writing that you withdraw the nomination.

What to do next

Check the app now, even without a letter. It shows whether HMRC's records for 2025/26 have been reconciled and whether a refund is waiting. Then look at your current tax code so that 2026/27 does not repeat the problem.