P800 Refund: What Your HMRC Tax Calculation Means

A P800 is a tax calculation from HMRC that shows whether you’ve paid the right amount of Income Tax through PAYE for a tax year.

It may tell you that you’ve overpaid and are due a refund, or that you’ve underpaid and need to pay more tax.

In this guide, you’ll learn why you may have received a P800, how to check the figures and claim a refund, what happens if you owe tax, and how to spot P800 refund scams.

Key points

• Check your P800 against your own records 🔍
  Compare the figures with your P60 form, payslips, P11D, and employment details before claiming a refund or paying an underpayment.
• You may need to claim your refund yourself 🖱️
  If HMRC says you’re due a refund, your P800 will explain how to claim it. You can do this through your Personal Tax Account or the official HMRC app.
• An underpayment may be collected through your tax code 📄
  If you owe less than £3,000 and meet the relevant conditions, HMRC will adjust your tax code so the amount is collected from your pay over the following tax year.
• Keep your financial records organised with ANNA 🚀
  ANNA brings your bookkeeping, income, expenses, invoicing, and tax admin together, making it easier to keep accurate records and check your tax position when HMRC sends a calculation.

A detailed look at the P800

HMRC sends the P800 after the end of the tax year, which runs from 6 April to 5 April. It usually arrives between June and October, though HMRC can send it any time up to the following March.

Before sending it, HMRC compares the tax you’ve paid with the amount you should have paid.

If you’ve paid too much, the P800 will tell you that you’re due a refund. If you’ve paid too little, it’ll explain the underpayment and how HMRC intends to collect the extra tax.

Here’s everything you can find on a P800:

🧠 Good to know

A P800 applies to people taxed through PAYE, such as employees and people receiving pensions. If you’re required to file a Self Assessment tax return, your tax calculation is normally dealt with through that return instead.

Why have I received a P800?

There are several reasons why the tax you’ve paid through PAYE might not match your final tax bill.

For example, you might have:

• Changed jobs during the tax year and had an incorrect tax code at some point
• Had more than one job, with your Personal Allowance split between your employments
• Started or stopped working during the year, changing how your income was taxed
• Received taxable benefits, such as a company car, which affected your tax bill
• Started receiving a State Pension alongside employment income

A P800 isn’t a penalty or an investigation; it’s a reconciliation.

HMRC only sends one when there’s a difference to explain, so plenty of people never get a P800 at all in a given year.

How to check your P800

Before claiming a refund or accepting an underpayment, compare your P800 with your own records.

Check:

• Your P60 to make sure your annual pay and PAYE tax deductions match
• Your payslips if you changed jobs or your income varied during the year
• Your P11D if you received taxable benefits from your employer
• Your employment details if you had more than one job or left an employer during the year
• Your tax code if you think your Personal Allowance or deductions may have been applied incorrectly

If something doesn’t match, contact HMRC and ask them to check the calculation before you take further action.

💡 Did you know?

Keeping your income and business records up to date makes it easier to check figures when you receive a tax calculation.

ANNA’s Auto Accountant helps you keep your financial information organised as you go, so you don’t have to piece everything together at the last minute.

How do you claim a P800 tax refund?

If your P800 says you’ve overpaid tax, you may need to claim the refund yourself online, as HMRC stopped automatically issuing most repayments in May 2024.

Your P800 will tell you which options are available. Usually, you can:

• Claim online with the reference number from your P800 and your National Insurance number
• Claim through your Personal Tax Account or the official HMRC app
• Request a cheque, either through the online service or by contacting HMRC

A cheque takes up to six weeks, while bank transfers usually arrive within five working days, though you’ll need a UK bank account for this option. If your P800 says HMRC will send you a cheque automatically, it should arrive within 14 days of the date on the letter.

Before entering any bank details, make sure you’re using the genuine gov.uk website or official HMRC app.

What if your P800 says you owe tax?

If the underpayment is less than £3,000, HMRC will usually collect it by changing your tax code for the following tax year. It then deducts the extra tax from your pay over the year rather than taking it as one lump sum.

For example, if your underpayment is £1,200 and HMRC collects it through your tax code over 12 months, it’ll deduct around £100 of additional tax each month.

The method may be different with larger underpayments. Your P800 should explain what you need to do and when you need to pay.

If you believe there may have been an error, check the figures against your records before accepting the calculation. If it still doesn’t look right, contact HMRC or speak to an accountant before paying.

How to spot a fake P800 or HMRC refund scam

P800 refunds are a favourite among scammers. The promise of money you weren’t expecting makes people drop their guard, and asking for bank details doesn’t seem suspicious.

You may receive a text or email claiming that you’re owed a refund and asking you to click a link to enter your personal or banking information.

If you get such a message, don’t click on the link. Instead, go directly to gov.uk or use the official HMRC app and check your Personal Tax Account. If there’s a genuine refund or tax calculation waiting for you, you should be able to find it there.

Be particularly careful if a message:

• Creates pressure by saying you have to claim immediately
• Comes from an unexpected mobile number or email address
• Asks for information that you wouldn’t normally provide to HMRC

Keep your tax records organised with ANNA

Cross-checking a P800 is far quicker when your income and expense records are already in order. If you’ve had several jobs, received taxable benefits, or had other income sources, finding the right figures can take time.

ANNA brings together your business account, bookkeeping, invoicing, and tax admin to help you keep your financial records organised year-round.

Here’s how ANNA helps:

• Dedicated business account: Manage your day-to-day business finances with ease
• Automatic bookkeeping: Keep your business income and expenses organised as transactions happen
• Receipt capture: Photograph and store receipts digitally, so you can quickly find supporting records when you need them
• Real-time tax estimates: See an up-to-date estimate of your tax position and the amount you may need to set aside
• Invoice creation and tracking: Create and manage invoices, and track what you’ve billed and what’s still owed
• Smart reminders: Never miss important tax and business deadlines
• Self Assessment filing: Prepare and submit your Self Assessment tax return directly to HMRC from the app
• Corporation Tax filing: Prepare and file your company’s Corporation Tax return and stay on top of your company tax obligations
• VAT registration and VAT filing: Register for VAT and easily manage your VAT returns
• 24/7 UK-based support: Get professional help whenever you need it

Sign up with ANNA today and keep your records ready for whatever HMRC sends your way.