Tax Refund UK 2026: How to Claim Your P800 Money Back

Tax refund UK searches spike every summer for a reason. Between roughly June and October, HMRC runs its annual PAYE reconciliation and millions of letters land on doormats telling people they paid too much tax last year. If a brown envelope has just arrived with a “P800 tax calculation” on the front, or you have a nagging suspicion you have been overtaxed after changing jobs, you are in exactly the right place. Getting your money back is usually far simpler than people expect, and in most cases you can do it yourself in under ten minutes without paying anyone a penny. The problem is that the process is buried in jargon, and a small army of scammers has built a whole industry around pretending to be HMRC.

A tax refund in the UK is issued when you have paid more Income Tax through PAYE than you actually owed. HMRC checks this automatically after the tax year ends on 5 April and sends a P800 tax calculation letter if you are due money back. You can then claim online through your Personal Tax Account and receive the refund by bank transfer within five working days.

What a UK Tax Refund Actually Is

PAYE, the system your employer uses to deduct tax from your wages, is a forecasting system. It spreads your Personal Allowance evenly across the year and assumes your income will carry on at the same rate until 5 April.

When reality does not match that forecast, the maths goes wrong. You might have been taxed as though you would earn a full year’s salary when in fact you only worked eight months. Or you might have been put on an emergency code that gave you no allowance at all for a few pay periods.

After the tax year ends, HMRC pulls together everything your employers and pension providers reported and recalculates what you should have paid. If the two figures do not match, you get a tax refund UK taxpayers know as a repayment, or an underpayment notice if it went the other way.

The 2026/27 figures the calculation is based on

Scotland uses a different set of Income Tax bands, so a Scottish taxpayer’s calculation will look different. National Insurance is not part of a P800 at all: employee Class 1 NI runs at 8% between £12,570 and £50,270 and 2% above that, and it is calculated per pay period rather than annually, which is why NI is rarely refunded.

Understanding Your P800 Tax Calculation

A P800 is a single sheet that sets out, in HMRC’s own arithmetic, what you earned, what you should have paid, and what you actually paid. It is not a bill and it is not a demand. It is a statement.

Read it line by line before you accept it. HMRC works from the information employers and pension providers submit, and that information is sometimes wrong or incomplete.

What to check on your P800

1. Every employment is listed. If you had three jobs last year and only two appear, the calculation is incomplete.
2. No employment is duplicated. Payroll changes sometimes create a phantom second employment with the same employer.
3. The pay figures match your P60s and P45s. Dig those out and compare the gross pay line.
4. Taxable benefits look right. A company car or private medical cover you gave back mid-year should be pro-rated, not charged for the full year.
5. Any state pension figure is the amount you were entitled to, not the amount you happened to receive in that calendar window.

If something is wrong, do not claim and hope for the best. Contact HMRC, tell them which figure you disagree with and what you believe the correct figure is. Understanding your tax code helps enormously here, and our guide to UK tax codes explained for 2026 walks through what each letter and number actually means.

Why You Might Be Owed Money

Overpayments are not unusual and they are not a sign you did anything wrong. These are the situations that generate the bulk of P800 refunds.

You changed jobs during the tax year

If your new employer did not receive your P45 in time, they may have used an emergency code. Emergency codes assume you have already used part of your allowance elsewhere, so you get taxed more heavily until the code is corrected.

You stopped working partway through the year

Someone who leaves a job in September has had tax deducted as though they would keep earning until April. They have almost certainly overpaid, because their unused Personal Allowance for the remaining months is sitting there unclaimed.

You had two jobs at once

Your allowance can only be applied to one employment. If it was allocated to the lower-paying job, you may have paid basic rate tax on income that should have been tax free. Learning to read a UK payslip properly is the fastest way to catch this while it is still happening rather than a year later.

You had unclaimed work expenses

Tax relief on job expenses is one of the most under-claimed reliefs in the UK. Typical examples include the flat rate uniform allowance, which is £60 a year for most occupations and higher for some trades, professional subscriptions to an approved body, and mileage in your own vehicle where your employer paid less than the approved rate.

You were on an emergency or wrong tax code all year

Codes ending in W1, M1 or X are non-cumulative. They treat every pay period in isolation and never look back to correct earlier overpayments, so the error simply compounds until the year ends.

Worked example: leaving a job in October

Priya earns £36,000 a year and leaves her job at the end of October, taking two months off before starting somewhere new in January. By October she has been paid £21,000 gross and has had tax deducted as though she were on track for the full £36,000.

Because PAYE is cumulative, her code should partly correct itself when she rejoins in January. But if her new employer puts her on a month 1 code, it will not. Her total earnings for the year come in around £30,000, so she has effectively been taxed on a projected £36,000 for part of the year. HMRC picks this up after 5 April and issues a P800 showing a few hundred pounds due back.

How to Claim Your Tax Refund Step by Step

If your P800 says you can claim online, this is the whole process.

1. Find your reference number. It is printed on the P800 letter. You will also need your National Insurance number.
2. Go to the official service. Search GOV.UK for “check how to get your Income Tax refund” and use the link on the GOV.UK page. Type the address yourself rather than following a link from a message.
3. Sign in with Government Gateway. If you have never set one up, you can create an ID during the process. Have your NI number and a form of identity to hand.
4. Check the calculation on screen against the figures on your P60s and P45s.
5. Choose bank transfer. You will need a UK account number and sort code in your own name.
6. Submit and note the confirmation. You should see an acknowledgement screen. Screenshot it.

You can also claim through your Personal Tax Account or the HMRC app, which is often the easiest route if you already have the app installed for checking your tax code.

Checklist before you claim

• P800 letter with reference number
• National Insurance number
• P60 for the relevant tax year, and any P45s
• Bank account details in your own name
• Government Gateway user ID and password

How Long a Tax Refund Takes

If you are owed tax for more than one year and HMRC is sending a cheque, you get a single cheque for the whole amount rather than one per year.

What to Do If You Have Not Had a P800

No letter does not automatically mean no refund. HMRC only issues a P800 when its automated reconciliation flags a mismatch, and it works from what employers reported. If the underlying reason for your overpayment is something HMRC does not know about, such as unreimbursed work expenses, nothing will be flagged.

In that situation you claim proactively rather than waiting.

• Work expenses under £2,500 a year: use the GOV.UK service for claiming tax relief on work expenses, or form P87.
• Work expenses over £2,500 a year: you will normally need to register for Self Assessment.
• Marriage Allowance: if one partner earns under the Personal Allowance and the other is a basic rate taxpayer, transferring £1,260 of allowance is worth up to £252 in the current year, and you can backdate four years.
• Left the UK partway through a tax year: form P85 tells HMRC you have gone and triggers a recalculation.
• Overpaid on a pension lump sum: forms P53, P53Z, P55 or P50Z depending on your circumstances.

If your tax affairs are getting complicated enough that you are weighing up filing a return, it is worth building some basic financial literacy alongside the admin. Coffee & Study’s finance and accounting courses cover the bookkeeping and spreadsheet skills that make managing your own tax position far less daunting.

Claiming Refunds for Earlier Years

The general time limit for reclaiming overpaid Income Tax is four years from the end of the tax year in question. Since the 2026/27 tax year began on 6 April 2026, that means claims for 2022/23 and later are still open, and anything from 2021/22 or earlier has now expired.

This matters most for things like the uniform allowance, professional subscriptions and Marriage Allowance, where a four-year backdated claim can be worth several hundred pounds in one go. Each year has to be claimed separately, but the same form usually covers them all.

Spotting Fake HMRC Refund Messages

Tax refund scams are among the most common frauds in the UK, and they surge in exactly the months when genuine P800s are going out. The scammers know that a message about free money gets clicked.

The single most useful thing to remember is this: a P800 tax calculation only ever arrives by post. HMRC does not send P800s by text or email, and it does not put a link to a refund claim form in an unsolicited message.

Red flags

• A text or email announcing a specific refund amount, often an oddly precise figure designed to look computer-generated
• Any link asking you to “verify” bank details, card numbers or a card security code. HMRC never asks for card details to pay you
• Urgency: “claim within 24 hours or forfeit your refund”. Genuine refunds do not expire in a day
• A sender address that is close to but not exactly a gov.uk domain
• Phone calls demanding immediate action or threatening arrest

What to do instead

Never click the link. Open a browser, type gov.uk yourself, sign in to your Personal Tax Account and see whether a genuine repayment is showing. Any real refund will be visible there.

You can report suspicious texts by forwarding them to 7726, which is free on all UK networks, and report phishing emails to HMRC through the reporting address published on GOV.UK. If you have already entered bank details on a fake site, call your bank on the number printed on the back of your card straight away and ask them to block any suspicious payments.

A note on refund agents

Some companies advertise heavily to handle refund claims for you, typically taking a percentage of whatever comes back. They are legal, but they are not necessary. Everything described in this guide is free and takes minutes. Be especially careful about signing anything that appoints a company as your nominee, because that can direct future refunds to them rather than to you.

Common Mistakes to Avoid

Assuming the P800 is automatically correct

HMRC computes from what it was told. If an employer filed the wrong figure, or a benefit was reported for a full year when you only had it for three months, the calculation inherits that error. Check it against your own P60 before accepting anything, and challenge it if the numbers do not add up.

Ignoring the letter because it looks like a bill

Plenty of people leave HMRC envelopes unopened for weeks, assuming bad news. A P800 is just as likely to be money coming your way. Open it, and if it says you can claim online, act while the reference number is to hand.

Clicking a link in a refund text

This is the mistake that costs people real money. The message looks plausible, the site looks like Government Gateway, and the bank details you type go straight to a criminal. Always navigate to gov.uk yourself. Every genuine refund is visible in your Personal Tax Account.

Missing the four-year window

People often discover the uniform allowance or Marriage Allowance years after they first became eligible, then only claim the current year. If you were eligible in earlier years, backdate the claim. Once a year falls outside the four-year limit it is gone permanently.

Not fixing the underlying tax code

A refund cleans up last year. It does nothing about this year. If the wrong code is still on your payslip, you will simply overpay again and wait another twelve months. Check the code on your current payslip and get it corrected through your Personal Tax Account.

Frequently Asked Questions

How do I know if I am due a tax refund in the UK?

The clearest signal is a P800 tax calculation letter from HMRC, which arrives by post after the tax year ends. You can also check your Personal Tax Account on GOV.UK at any time, where your income, tax paid and tax code for the year are all shown. If you changed jobs, had a gap in employment, worked two jobs or were on an emergency code, it is worth checking even without a letter.

How long does a tax refund take to reach my bank account?

If you claim online through the bank transfer service, HMRC states you will normally receive the money within five working days. If you request a cheque online instead it takes around six weeks. Where HMRC decides to issue a cheque automatically, it should arrive within fourteen days of the date on your letter without you doing anything at all.

Can I claim a tax refund from previous years?

Yes. The standard time limit is four years from the end of the relevant tax year. In the 2026/27 tax year that means 2022/23 onwards is still within time. Backdating is particularly worthwhile for the flat rate uniform allowance, professional subscriptions and Marriage Allowance, where four years claimed together can amount to a meaningful sum.

Does HMRC ever text or email about a tax refund?

HMRC does not send P800 tax calculations by text or email, and it does not send unsolicited messages containing a link to claim a refund. Treat any such message as a scam, do not click the link, and check your Personal Tax Account directly by typing gov.uk into your browser. Forward suspicious texts to 7726.

Do I need to pay a company to get my tax refund?

No. Claiming is free and, for a straightforward P800, takes only a few minutes online. Refund agents typically keep a percentage of your money and some ask you to sign a nominee agreement that redirects future refunds to them. If your situation is genuinely complex, a qualified accountant on a fixed fee is usually a better option than a percentage-based refund firm.

Will I get National Insurance back too?

Usually not. National Insurance is worked out separately for each pay period rather than cumulatively across the year, so the sort of mid-year change that causes an Income Tax overpayment does not normally create an NI overpayment. NI refunds do happen, most often where someone had multiple jobs and paid over the annual maximum, but they are handled separately from a P800.

Sorting out your tax is often the first step in a bigger reset, and plenty of people who discover they have been on the wrong code for a year also discover they have been underpaid for their role. If that sounds familiar, browse the current openings on UK Jobs Alert to see what your skills are worth in 2026, and check our guide to what a competitive salary really means in the UK before your next negotiation.