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P800 Tax Refund Checker

HMRC reconciles millions of PAYE records after each tax year and writes P800 letters where tax was overpaid or underpaid. This checker mimics that arithmetic from your P60 numbers so you know what to expect — before, or instead of, waiting for the letter.

It is deliberately simple: one employment income figure and the tax paid against it.

Written by RefundCalculator Editorial TeamLast checked

Check the likely P800 outcome

HMRC reconciles a year after it ends. Compare your P60 tax against the year's rates to preview the direction — refund or underpayment.

Where do you pay income tax?

When P800 letters actually arrive

HMRC runs its end-of-year reconciliation after the tax year closes, and P800s flow out in waves between June and November. Simple PAYE cases come first; anything involving benefits in kind, two jobs or the state pension lands later. If you have a Personal Tax Account the same calculation appears there first, often weeks before paper post — and you can claim the refund online the moment it shows.

What triggers HMRC's reconciliation

  • Emergency or wrong tax codes that stayed live for months.
  • Company benefits (car, medical cover) coded late or coded twice.
  • Two overlapping employments with duplicated Personal Allowance.
  • Taxable state benefits (state pension, Carer's Allowance) clashing with a workplace code.
  • A job started or ended mid-year that payroll estimated wrongly.

Genuine P800 versus refund scams

  • Real P800s arrive by post or inside your Personal Tax Account — never as a texted link.
  • HMRC never asks for card details, banking passwords or a 'release fee' to pay a refund.
  • Genuine refunds are paid by bank transfer or cheque, in full, with no agent.
  • If a message pressures you to act before a deadline today, it is not HMRC.

What this estimate can't tell you

  • A P800 uses HMRC's complete record — multiple jobs, benefits, state pension — which this tool cannot see.
  • Underpayments under £3,000 are usually coded out next year, not demanded in one go.
  • Never pay anyone to 'release' a P800 refund — HMRC pays direct, free.

The free HMRC route

Everything this calculator estimates can be claimed directly from HMRC at no cost — usually online in a few minutes or via a short form. Refund companies charge a percentage of money that is already yours. We never handle claims and are not affiliated with HMRC.

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