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P800 Refund

Independent UK guidance for P800 refunds and HMRC letters.

Official HMRC links matter. This site explains the process in plain English and points readers towards official GOV.UK routes.

Letter guide

P800 Letter Sample: Where to Find the Reference Number

Independent UK guidance for the 2025/26 tax year. We are not affiliated with HMRC or GOV.UK, and this sample is illustrative only.

Quick answer: Where to find your reference number

Your P800 reference number is usually shown near the top of the letter, often labelled 'Reference' or 'Our reference'. It looks something like P800 / 1234 5678 90. You'll need it when claiming online on the official GOV.UK service.

Ready to claim?

Once you've found your reference number, use the official GOV.UK service to claim your refund safely. Step-by-step claim guide →

Readers often search for a P800 letter sample because they want to know whether the letter looks genuine, where the P800 reference number appears, and what details matter before using the official GOV.UK route for the 2025/26 tax year.

This page shows a simplified sample layout, points out the kind of information you should look for, and links you back to the right next step if you need to claim a P800 refund online or check the official GOV.UK route first. If you want the wider starting point, return to the P800 refund homepage.

Check the tax year and overpayment wording first.
Confirm the reference number only on an official .gov.uk page.
Use the sample as a guide, not as a substitute for your own letter.

Illustrative P800 letter sample

This is a simplified sample designed to show the kind of layout readers usually mean when they search for a P800 letter sample. It highlights the reference area without copying an official HMRC letter exactly.

HM Revenue and Customs

Tax calculation

PAYE & Self Assessment

BX9 1AS

United Kingdom

Your details

Name: Alex Taylor

National Insurance number: AB 12 34 56 C

Tax year: 6 April 2025 to 5 April 2026

Find this on your letter

Reference area

P800 / 1234 5678 90

This is the kind of reference information readers often need when using the official refund route.

Tax calculation summary

Total taxable income
GBP 35,000
Tax due
GBP 4,486
Tax already paid
GBP 5,200
Overpayment
GBP 714

Safety checklist before you use the reference number

Safer signs

  • Check that the letter clearly shows the tax year and the calculation outcome.
  • Check that the address and claim route match current GOV.UK guidance.
  • Check that any repayment step takes you to an official .gov.uk page.

Scam signs

  • An SMS or email pushes you to click a refund link immediately.
  • The website asks for bank details or Government Gateway login too early.
  • The address bar does not clearly end in .gov.uk.

What to check on your real P800 letter

Start with the tax year, the amount shown, and whether the wording says you overpaid or underpaid tax. If you are still working out what the calculation means, read What Is a P800? before moving to the claim stage.

  • Check that the tax year matches the letter in front of you.
  • Check whether the wording refers to an overpayment, underpayment or a repayment already being issued.
  • Check whether the letter tells you to claim online or says HMRC will send a cheque automatically.

Where the reference number matters

GOV.UK says online claims usually require the reference number from your P800 letter and your National Insurance number. That is why readers often search for sample letters: they want to know what they are looking for before they open the official service.

Once you have found the reference on your real letter, use the P800 online claim guide and only enter it on the correct GOV.UK route.

How to enter this on GOV.UK →

Red flags to watch for

A sample page like this should make you more cautious, not less. If a site asks for your reference number, banking details or Government Gateway sign-in too early, stop and verify the address first.

  • The website does not clearly end in .gov.uk.
  • You were sent to the page from an unexpected SMS, email or WhatsApp message.
  • The page pressures you to act immediately or says the refund will be lost today.

If you want to verify the route before doing anything else, use the GOV.UK P800 refund links guide.

Lost your P800 letter?

If you cannot find your P800 letter, you are not alone. HMRC sends these tax calculation letters to millions of taxpayers each year, and they can be misplaced, recycled with other post, or never arrive at all.

Here is what you can do:

  • Check your Government Gateway account. Log in at the official GOV.UK sign-in page. Some taxpayers can view their tax calculation online, including the reference number, even if the paper letter is missing.
  • Check the tax year. P800 letters for the 2025/26 tax year (ending 5 April 2026) are expected from June 2026 onwards. If you have not received one yet, it may simply not have been issued. See the P800 timeline guide for expected dates.
  • Contact HMRC. If you believe a P800 should have been sent but you never received it, you can call the HMRC Income Tax helpline. They can confirm whether a calculation was issued and, in some cases, reissue the letter.
  • Do not guess the reference number. If you are trying to claim online and cannot find the reference, do not make one up. An incorrect reference may delay your refund or flag your claim for additional checks.

If you have lost your letter and need to verify the official route before contacting HMRC, use the GOV.UK P800 refund links guide.

Where to go next

Claim a P800 refund online safelyUse the official route only after checking the details on your letter.Track my refund timingCompare online payment timing, cheque timing and what to expect next.What your P800 letter meansUnderstand the calculation and find the right next step.What is a P800 letter?Read the plain-English explanation before using the letter details or refund route.

Sources

This sample page is based on current official guidance and should be checked again if HMRC or GOV.UK updates the process.

GOV.UK: If your tax calculation letter (P800) says you are due a refundhttps://www.gov.uk/p800refundUsed for the official refund route, the reference number requirement and current repayment guidance.GOV.UK: Claim a refund for overpaid taxhttps://www.gov.uk/p800/refundUsed for the official claim path readers often try to reach after checking the letter details.

Common questions

What is a P800 reference number?

It is reference information shown on the P800 tax calculation and may be needed when you use the official GOV.UK refund route.

How do I find my P800 reference number?

Look for a reference or "Our reference" section near the top of your P800 letter. It usually contains a combination like P800 followed by numbers. Use this number only on the official GOV.UK website.

How do I check my P800 reference number?

Check the reference area on the letter itself, match it with the tax year shown, and only enter it on the official GOV.UK route if the wording on your letter tells you to continue.

Is this an official HMRC letter?

No. This page shows an independent sample layout to help you recognise the kind of details a P800 letter contains. It is not an official HMRC document.

What should I check before using the reference number online?

Check that you are on the correct GOV.UK route, that the tax year matches your letter, and that the reference is being entered on an official .gov.uk page.

What if I cannot find the reference number on my P800?

Pause before entering anything online. Recheck the reference area, the tax year and the wording on your letter, then compare it with the GOV.UK route guide. If the letter still does not match what the online service expects, use the official HMRC guidance instead of guessing.

What should I do if I have lost my P800 letter?

Check your Government Gateway account online first — some taxpayers can view their tax calculation and reference number there. If it is not available online, contact the HMRC Income Tax helpline. They can confirm whether a calculation was issued and may be able to reissue the letter. Do not guess the reference number when claiming online.

Last updated: 4 June 2026 · Reviewed by James Wells