What Is a P800 and How Do You Claim the Tax Refund You’re Owed?

If a letter from HMRC headed “P800” has landed on your doormat, or you have heard the term and wondered what it means, this guide is for you. A P800 is HMRC’s way of telling you that, after totting up your tax for the year, the sum did not come out exactly right. Sometimes that means a refund is on its way. Sometimes it means you owe a little. And sometimes a refund is due but HMRC has not worked it out at all, because the information that would trigger it is missing.

Here is what a P800 is, what to do when you get one, and how to make sure you actually receive any money you are owed.

What is a P800?

A P800, also called a tax calculation, is a statement HMRC issues after the end of a tax year when it thinks you have paid the wrong amount of tax through PAYE. It compares the tax you actually paid against what HMRC believes you should have paid, and shows the difference.

It is only issued to people taxed through PAYE, not those who complete a self-assessment tax return, since the return already squares everything up.

Why might you get one?

HMRC typically issues a P800 when something meant your tax did not balance over the year. Common reasons include:

• You changed jobs and your tax was not fully reconciled across them.
• You had more than one job or pension at the same time.
• You were on an emergency tax code for a period.
• You started or stopped receiving taxable benefits, such as a company car.
• Your income changed in a way PAYE did not fully capture.

What does a P800 tell you?

A P800 will say one of three things:

1. You are due a refund. HMRC has worked out you overpaid and will tell you how to get the money back, often online, sometimes by cheque if you do not claim it online within a set period.
2. You owe tax. You underpaid, and HMRC will usually collect it by adjusting your tax code for a future year, so it is spread out rather than demanded in one lump.
3. Everything balanced. Less common to receive, but it confirms the year was correct.

If your P800 shows a refund, do not ignore it. In many cases you need to take a step to claim it, for example confirming your bank details online, and if you do not, the refund can be delayed.

The catch: not everyone who is owed gets a P800

This is the part people miss. A P800 is only generated when HMRC’s own systems spot a mismatch. If you are owed money because of work expenses you have never claimed, such as uniform, mileage, tools or professional fees, HMRC has no way of knowing, so no P800 is issued and no refund appears. The money simply sits unclaimed.

In other words, no P800 does not mean you are not owed. It often just means the trigger that would create one has not happened, because you have not yet told HMRC about your expenses.

How to claim a tax refund

If you have a P800 showing a refund, follow the instructions on it, usually through your HMRC online account, and make sure your details are correct so the payment can reach you.

If you do not have a P800 but believe you have overpaid, perhaps because of unclaimed expenses or a wrong tax code, you need to make a claim to prompt HMRC. That means submitting the relevant details, often on form P87 for expenses, with evidence to support it.

TaxPro does exactly this. We look across your recent tax years, identify overpayments whether or not HMRC has issued a P800, and claim back everything you are owed in one go, including expenses HMRC would never refund on its own. We deal with HMRC directly and work on a no win, no fee basis, so a percentage fee only applies if a refund is secured.

How long does a refund take?

Once your claim is submitted to HMRC, the refund itself usually comes through in around 10 days, and the whole process from starting your claim to being paid typically takes around 8 to 10 weeks.

Frequently asked questions

Is a P800 a bill or a refund?

It can be either. It shows whether you overpaid (refund due) or underpaid (tax owed) for the year.

I never got a P800 but think I overpaid. What now?

You can still claim. A P800 is only one route. If your overpayment is due to unclaimed expenses, you usually have to make a claim to trigger the refund.

Is a P800 letter or text genuine?

Be careful. Scammers impersonate HMRC with fake refund texts and emails. HMRC will not ask for your bank details out of the blue by text or email. If in doubt, check through your official HMRC online account rather than clicking links.

Can I get a refund for past years?

Yes, claims generally cover the current tax year plus the previous four.

Make sure you actually get what you are owed

Whether or not you have had a P800, the only way to be sure you have received every refund due is to check your recent years properly.

Start your claim with TaxPro and we will find any overpaid tax and unclaimed expenses and reclaim them for you, on a no win, no fee basis.

TaxPro works on a no win, no fee basis. If we secure your refund, our fee for PAYE claims is 37.5% plus VAT (minimum £50 plus VAT). If there is no refund, there is nothing to pay.

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