P800 Tax Refund UK 2026: What Your HMRC Letter Means and How to Claim

Every summer and autumn, HM Revenue and Customs sends out millions of P800 tax calculation letters, and searches for gov uk P800 refund spike as people try to work out whether the letter in their hand means money is coming back to them. If you have received one, the short answer is encouraging: a P800 usually means HMRC has checked your tax for the year and found a difference between what you paid and what you actually owed. For many workers that difference is a refund. This guide explains what a P800 tax refund is, why you might be owed one, how to claim it online in minutes, how long the money takes to arrive, and how to protect yourself from the refund scams that circulate at this time of year. All figures are based on the 2026 UK tax rules.

What is a P800 tax calculation?

A P800 is a tax calculation letter from HMRC. It is sent to people taxed through PAYE, which covers most employees and many pension recipients, when HMRC’s end of year reconciliation finds that the tax collected through your payslip did not match the tax you actually owed. The letters normally go out between June and November, covering the tax year that ended on 5 April.

The letter sets out your income from employment, pensions and taxable benefits, the allowances you were entitled to, the tax you paid, and the tax HMRC believes you should have paid. If you paid too much, the P800 tells you how to claim a refund. If you paid too little, it explains how the underpayment will be collected. You cannot request a P800; HMRC issues them automatically. If you think you are owed tax back but have not received a letter, you can check your position through your Personal Tax Account or the HMRC app at any time.

Why you might be owed a tax refund

Overpayments through PAYE are surprisingly common, and they usually come down to your tax code. Common reasons include: starting a new job and spending months on an emergency tax code, having more than one job or pension so your Personal Allowance was split incorrectly, being made redundant or leaving work part way through the year, retiring or taking a flexible pension withdrawal that was taxed at an emergency rate, and claiming allowable work expenses such as professional fees or uniform laundering that were never reflected in your code. Our guide to UK tax codes explains how to read your code and spot when it is wrong before an overpayment builds up.

The size of a P800 refund varies enormously. A few weeks on an emergency code might mean a refund of under a hundred pounds, while someone who lost several months of Personal Allowance across two jobs can be owed well over a thousand.

The 2026 tax figures behind your calculation

Your P800 is worked out against the standard UK income tax bands. For the 2026 rules these are:

Employees also pay National Insurance at 8% on earnings between 12,570 GBP and 50,270 GBP and 2% above that, although National Insurance is not reconciled through the P800 process. If you want to sanity check the numbers on your letter against your payslips, our take home pay calculator guide walks through exactly how tax and National Insurance are deducted each month.

How to claim your P800 refund on GOV.UK

If your P800 says you are due a refund, the fastest route is to claim online. Go to GOV.UK and search for claim a tax refund, or sign in directly through your Personal Tax Account or the free HMRC app. You will need to sign in with your Government Gateway user ID, and the service will show the refund waiting for you along with a reference number from your letter.

Once you confirm your bank details, HMRC pays the refund directly into your account. You do not need to use any third party claims company, and you should never pay a fee to receive a P800 refund. Agents that advertise tax refund services typically take a large cut of money you could claim yourself in under ten minutes.

If you do nothing, HMRC will usually send a cheque automatically, but only after waiting to see whether you claim online first. Claiming online is quicker and avoids the risk of a cheque going to an old address.

How long does a P800 refund take?

Timescales depend on how you claim:

If nothing has arrived after these windows, contact HMRC on the number shown on GOV.UK rather than any number sent to you by text or email. You have four years from the end of the relevant tax year to claim a refund, so money from earlier years is not automatically lost, but it does not sit there earning interest either, so it is worth acting promptly.

What if your P800 says you owe tax?

Not every P800 is good news. If you underpaid, HMRC will normally collect the money automatically by adjusting your tax code for the following year, which spreads the repayment across your payslips. For larger amounts, or if you no longer pay tax through PAYE, you may instead receive a Simple Assessment letter asking for direct payment. Check the calculation carefully before paying. If the employment or pension figures on the letter do not match your P60 or payslips, contact HMRC and ask them to review it. Errors do happen, particularly where someone has changed jobs several times. If money is tight, HMRC can usually agree a payment plan rather than taking the sum in one go.

Watch out for P800 refund scams

Refund season is also scam season. Fraudsters send texts, emails and WhatsApp messages claiming you have a tax rebate waiting and linking to a fake GOV.UK site that harvests bank details. The real HMRC never sends refund links by text or email, never asks for your card details to release a refund, and never demands payment through gift cards or transfer apps. If you receive a message like this, do not click the link. Forward suspicious emails to phishing@hmrc.gov.uk and texts to 60599, then delete them. The only safe way to claim is to type gov.uk into your browser yourself and sign in to your own account.

Put your refund to work

A P800 refund is your own money coming back, and it often lands at a useful moment. If the refund arrived because you were between jobs, it might be the buffer that funds your next move. You can browse live UK jobs updated daily on UK Jobs Alert, from part time and warehouse roles to office and council positions across the country. And if a wrong tax code caused the overpayment in the first place, take five minutes to check your current code so the same thing does not happen again next April.

Frequently asked questions

Is a P800 letter genuine?

A P800 arrives by post, never by text or email. If the letter quotes your correct details and directs you to GOV.UK rather than an unusual website, it is genuine. You can verify any refund by signing in to your Personal Tax Account directly.

How do I claim my P800 refund?

Sign in to GOV.UK through your Personal Tax Account or the HMRC app, follow the claim a tax refund service, and enter your bank details. Payment usually arrives within about five working days.

How far back can I claim a tax refund?

You can claim overpaid tax for up to four years after the end of the tax year in question. Beyond that the money is normally lost, so check old years while you still can.

Why did I get a P800 saying I owe money?

Usually because your tax code collected too little during the year, often after a job change, a company benefit, or a second income. HMRC typically recovers the shortfall by adjusting next year’s tax code.

Do I need an accountant or claims company?

No. Claiming a P800 refund is free and takes minutes online. Claims companies deduct fees, sometimes 30% or more, for doing what you can do yourself.

What if I never received my cheque?

Contact HMRC using the contact details published on GOV.UK. They can cancel the original cheque and reissue the payment, or pay it into your bank account instead.