A P800 letter from HMRC can mean extra cash in your pocket or a bill you didn’t expect to see. Millions of these letters go out every year once HMRC checks whether your Income Tax was paid correctly.
This guide breaks down what a P800 actually is, why HMRC sent you one the exact steps to claim your refund online, how long it takes to arrive and how to avoid falling for a common tax refund scam.
What Is a P800 Tax Calculation?
A P800 is a letter HMRC sends when the tax you paid during a tax year doesn’t match what you actually owed. It’s not a bill or a fine, it’s simply HMRC’s way of squaring up your Income Tax record after the tax year ends on 5 April.
HMRC usually sends P800 letters between June and October once employer and pension data has been processed. The letter tells you one of two things: you paid too much tax and are due a refund or you paid too little and need to pay the difference.
| Detail | Information |
| Sent by | HM Revenue and Customs (HMRC) |
| Typical timing | June to October (after tax year ends) |
| Covers | PAYE income employment or pension |
| Format | Letter by post sometimes flagged in your Personal Tax Account |
| Outcome | Refund due or tax owed |
If you’re self-employed and file a Self Assessment return a P800 does not apply to you. Self Assessment refunds work through a separate process.
Why Did You Receive a P800 Letter?
A P800 is triggered by a mismatch between tax paid and tax owed usually caused by a change in your income or circumstances during the year. HMRC’s PAYE system doesn’t always catch these changes in real time so a correction gets made afterward.
Common reasons a P800 lands on your doorstep include:
- Starting or leaving a job partway through the tax year
- Having more than one job or pension at the same time
- Receiving Jobseeker’s Allowance or another taxable benefit
- Being on the wrong tax code for part of the year
- Company benefits changing such as a car allowance or health insurance
- Claiming Marriage Allowance or other tax reliefs
- Starting or stopping a workplace pension
Any of these can shift your total taxable income enough that HMRC needs to rebalance what you’ve paid.
How to Read Your P800 Letter
Your P800 breaks down exactly how HMRC reached its figure and understanding it helps you spot errors early. The letter lists your total income, tax already paid, and tax actually due for the year in question.
Here’s what a typical breakdown looks like:
| Line item | Example figure |
| Total income for the year | £28,500 |
| Tax already paid | £4,200 |
| Tax actually due | £3,750 |
| Result | £450 refund due |
Check the income figure against your P60 or final payslip for that tax year. If the numbers don’t match your records contact HMRC before accepting the calculation, since the refund or bill is based entirely on this figure.
How to Claim Your P800 Refund Online
Claiming online is the fastest route, most refunds processed this way land within 5 working days. You’ll need a Government Gateway ID to access your Personal Tax Account, where the claim is completed.
Step 1: Sign In to Your Personal Tax Account
Go to GOV.UK and sign in using your Government Gateway ID. This is the same login used for checking your tax code or Self Assessment records.
Step 2: Locate the P800 Notification
Find the P800 notification under your tax overview or messages section once you’re signed in. This confirms the exact refund figure HMRC has calculated.
Step 3: Select “Claim Your Refund Online”
Choose this option to start the claim process directly from your account, no separate form or download needed.
Step 4: Confirm Your Bank Account Details
Enter or confirm your bank account details so HMRC can send the refund by direct transfer instead of a cheque.
Step 5: Submit and Save Your Confirmation
Submit the claim and save the confirmation reference for your records, this is useful if you need to follow up later.
If you don’t claim online within 21 days of the letter’s date, HMRC automatically sends a cheque instead. This takes longer to arrive and requires a trip to the bank.
How Long Does a P800 Refund Take to Arrive?
Refund timing depends entirely on how you claim it, online transfers are faster than posted cheques in almost every case. Most people see their money within a few weeks of the date on their P800 letter, though the exact wait varies based on the claim method chosen and how quickly HMRC processes it.
| Claim method | Typical processing time |
| Online claim, bank transfer | 5 working days |
| No online claim, cheque by post | Up to 6 weeks |
| Claim after 21-day window | Cheque issued automatically |
Claiming online through your Personal Tax Account remains the quickest way to get paid, avoiding the extra wait and the trip to the bank that comes with a posted cheque. If it’s been longer than 6 weeks with no refund and no cheque, contact HMRC directly through the official helpline rather than a third-party number found online or in a text message.
What If You Owe Money Instead of Getting a Refund?
Not every P800 brings good news, sometimes it shows you owe HMRC money due to underpaid tax. This isn’t a penalty, it’s simply the balance still due for that tax year.
HMRC typically recovers underpaid tax in one of these ways:
- Tax code adjustment, the amount is collected gradually through your next year’s payslips
- Direct payment, for larger amounts, HMRC may ask for payment by a set deadline
- Payment plan, you can request to spread payments if the amount is difficult to pay in one go
If you disagree with the underpayment figure you have the right to query it with HMRC before any adjustment is made. Keep your P60 and payslips handy as evidence.
P800 Refund Scams How to Stay Safe
Tax refund scams spike every year around the same months HMRC sends genuine P800 letters making it easy for fraudsters to blend in. HMRC never sends refund notifications by text message or email asking you to click a link.
Watch for these warning signs:
- Unsolicited texts or emails claiming a tax refund is “waiting”
- Links asking for bank details, card numbers, or passwords
- Urgent language pressuring you to act “within 24 hours”
- Requests for a small “processing fee” before releasing a refund
- Caller ID claiming to be HMRC asking for personal details over the phone
HMRC only confirms refunds through a P800 letter by post or your verified Personal Tax Account, never by unsolicited email, text, or phone call. If you’re unsure, go directly to GOV.UK and check your account rather than clicking any link sent to you.
What to Do If You Haven’t Received a P800 but Think You’re Owed a Refund
You don’t have to wait for a P800 to arrive if you believe you’ve overpaid tax, you can check and claim directly through your Personal Tax Account at any time. This is useful if you changed jobs, stopped working, or think a past tax code was wrong.
Check Online First
Log in to your Personal Tax Account and review your tax calculation for the relevant year. This gives you the fastest answer without waiting for HMRC to send anything by post.
Use Form P50
Use this form if you’ve stopped working and won’t have taxable income again this tax year. It lets HMRC process your refund before the tax year officially ends.
Use Form P87
Use this form if you’re claiming tax relief on job expenses that affected your tax, such as uniform costs, tools, or working from home.
Contact HMRC Directly
Call HMRC directly if none of the online options cover your situation. This works well for older overpayments or unusual circumstances that don’t fit a standard form.
Claims can generally be backdated up to 4 tax years, so it’s worth checking even if the overpayment happened a while ago.
Final Thoughts
A P800 letter is simply HMRC confirming whether your Income Tax was paid correctly for the year, nothing to fear either way. Always check the figures against your P60 or payslips before accepting the calculation. Claim online through your Personal Tax Account for the fastest refund, usually within 5 working days or expect a check if you miss the 21-day window.
If you owe money instead, HMRC will either adjust your tax code or agree to a payment plan. Stick to official GOV.UK channels only, HMRC never asks for bank details by text or email.
FAQs
What Does P800 Stand For?
P800 isn’t an acronym, it’s simply the reference name HMRC uses for its End of Year Tax Calculation letter.
How Do I Know If My P800 Letter Is Genuine?
Genuine P800 letters arrive by post or appear in your verified Personal Tax Account HMRC never sends refund alerts by text or email link.
Can I Claim My P800 Refund Without A Government Gateway Account?
Yes you can call HMRC directly and request a cheque if you don’t want to set up online access.
What Happens If I Ignore My P800 Letter?
If you don’t claim online within 21 days, HMRC automatically issues a cheque so you won’t lose the refund, but it will take longer to arrive.
Do I Need A P800 If I’m Self-Employed?
No Self Assessment taxpayers get refunds through their tax return, not through a P800.
How Far Back Can I Claim A Missed Tax Refund?
You can typically claim back up to 4 tax years from the current one.
Why Do I Owe Tax On My P800 Instead Of Getting A Refund?
This usually happens due to an incorrect tax code, extra untaxed income, or a change in benefits during the year.
Can A P800 Refund Be Paid Into Someone Else’s Bank Account?
No HMRC only pays refunds into an account matching your name for security reasons.
What’s The Difference Between A P800 And A P60?
A P60 is issued by your employer showing total pay and tax for the year a P800 is HMRC’s own calculation confirming whether that tax was correct.
Who Do I Contact If My P800 Refund Hasn’t Arrived?
Contact HMRC directly through the official number listed on GOV.UK never a number found in a text message or unofficial website.
