NHS Overpayment Recovery Checker: Gross or Net?

Told by NHS payroll that you were overpaid? Find out roughly how much of the gross figure you actually received after tax, National Insurance and pension, how recovery usually works, and what repayment you could afford to propose.

Want the law first? Read NHS Overpayment of Wages: What Are Your Rights?

The overpayment

The gross figure on the payslips or in the letter, before tax, National Insurance and pension.

Leave blank if all of it was paid since 6 April 2026.

If you have a letter or email with a figure, enter it and we will compare it with our estimate.

Your normal pay

Your usual yearly salary before the overpayment. We use it to work out your tax rate on the extra money.

Working out a repayment you can afford

Rent or mortgage, bills, food, travel, childcare and debt payments.

Share of your spare money to put towards it

What you actually received

Enter the gross overpayment and your normal pay

You will see roughly how much of the gross figure reached your bank account after tax, National Insurance and pension, how recovery usually works for this tax year and earlier ones, and a repayment schedule you could propose.

If you need to write to payroll

Turn this into letters

This checker is free and stays free. The Overpayment Response Pack drafts the letters to ask for the calculation, query it, ask to pause deductions or propose a plan, from your own figures. It costs £7.99 one-off for 90 days of access, with no subscription.

Assumptions

  • Net received is take-home pay with the overpayment minus take-home without it, so it uses your marginal tax, National Insurance and pension rates.
  • 2026/27 tax, National Insurance, pension and student loan rules are used for every year, so earlier years are an approximation.
  • Standard tax code and a full year in the same job. No other income, salary sacrifice or benefits in kind.
  • Your payslips and payroll's own calculation are the final word, and trusts' policies differ on notice, limits per payslip and hardship.
  • General information only, not legal advice. Your union, ACAS or a solicitor can advise on your own case.

Free download: sample letter to query an NHS overpayment

A polite letter asking payroll for a written breakdown, ready to adapt. We'll also email you when the rules or deadlines change on redundancy, disciplinary, regrading and overpayments.

Free. Independent, not affiliated with the NHS. Every email has an unsubscribe link. See our privacy policy.

Short answer

You should generally only be asked to repay what you actually received: the net amount, not the gross figure on your payslip. On a £38,000 salary in England, a £1,000 gross overpayment leaves about £642 in your bank account. Within the same tax year payroll can usually correct the tax and National Insurance, so the net figure is what is recovered. If it is only found after the tax year has ended, the trust may ask for the gross amount and correct your tax record separately. Either way you can ask for the calculation in writing and propose an affordable plan.

⚠General information, not legal advice

Trusts, ICBs and health boards each set their own overpayment policy, so limits per payslip, notice and hardship rules differ. This tool gives a planning estimate. Your union, Acas or a solicitor can advise on your own case.

NHS overpaid wages: do I repay gross or net?

A payslip shows gross pay, before Income Tax, National Insurance and pension. What reached your bank account was the net amount. Our guide to your rights on NHS overpayment explains that you should generally only be asked to repay what you actually received, that the tax and National Insurance side is for your employer to sort out with HMRC, and that a request which appears to exceed what you received is worth querying in writing before you agree to anything.

How much of an overpayment did you actually receive?

The share depends on your marginal tax rate and NHS Pension tier. These examples come from the same engine as the checker: £1,000 gross overpaid on top of each salary, England, in the NHS Pension Scheme, no student loan, with pension taken from the overpaid pay too.

Normal salaryIncome taxNational InsurancePensionNet received
£22,000 £187 £80 £65 £668
£30,000 £183 £80 £83 £654
£38,000 £180 £80 £98 £642
£52,000 £85 £20 £575 £320
£70,000 £350 £20 £125 £505

At higher salaries the overpayment can also push you across an NHS Pension contribution tier, which is why the pension figure can look large: in the tier model we use, the higher rate applies to all pensionable pay. Your payslips for the months concerned show what was really deducted.

Same tax year or earlier tax years: what changes?

From our guide, in practice most trusts recover the net figure if the correction happens within the same tax year, since payroll can correct the tax and National Insurance automatically. If an overpayment is only discovered after the tax year has ended, a trust may need to recover the gross amount and correct your tax record separately. Either way the principle is that you should not be left out of pocket for tax your employer needs to sort out with HMRC. If you have been asked for an amount that includes an earlier year, ask payroll, in writing, how tax, National Insurance and pension for that year are being corrected.

Can the trust take it all from one payslip?

Acas's guidance is that an employer should not deduct money from your wages without letting you know, should talk to you first and agree how it will be repaid, and should be flexible and fair, with a repayment plan, where the overpayment is large or covers a long period. The trust policies reviewed for our guide commonly set a limit on what can be taken from a single payslip without your agreement. That limit differs between employers, so ask for your trust's overpayment policy.

Repaying an NHS overpayment you can afford

The simplest honest method is: monthly take-home, minus essential outgoings, gives your spare money; offer a share of it. For example, £2,400 repaid at £200 a month clears in 12 months. Ask for the plan to be confirmed in writing with the monthly amount, start date and end date. If you have little or nothing spare, say so specifically, involve your union or staff-side representative, and consider free debt advice from StepChange or Citizens Advice.

What to ask payroll for

  • ✓ A written explanation of how the overpayment arose and the period it covers
  • ✓ A pay-period-by-pay-period calculation, checked against your own payslips and contract
  • ✓ Confirmation of whether the figure is net or gross, and how tax and National Insurance are being corrected
  • ✓ A copy of the trust's overpayment recovery policy, including any limit per payslip and its hardship provisions
  • ✓ Written confirmation of any repayment plan: the monthly amount, start date, end date and total
  • ✓ Confirmation of how your NHS Pension record is being corrected, if pensionable pay was affected

If you have left the NHS

Once you have left there is no payroll to deduct from, so your former employer generally has to ask you to repay directly. Acas says that if a former worker refuses to pay back the money, the employer might make a court claim. You still have the normal rights of anyone facing a debt claim, including checking the amount, so respond promptly and ask for the calculation.

Sources

Employment Rights Act 1996, section 14, Acas: handling overpayments and our own overpayment rights guide, which reviews several trust policies. Our figures use the same tax, National Insurance, pension and student loan engine as the NHS Pay Calculator. See our editorial policy.

Why trust this checker

  • ✓ Net is calculated from the difference in take-home pay with and without the overpayment, so it follows your own marginal rates
  • ✓ Uses the same engine as our NHS Pay Calculator and the legal points in our overpayment rights guide, with the Employment Rights Act and Acas as sources
  • ✓ Says plainly where trusts differ and where earlier tax years are an approximation
  • ✓ Runs in your browser: your figures are not sent to a server
  • ✓ Updated October 2026

Related guides & tools

NHS Overpayment of Wages: Your Rights

The law and typical trust practice behind this checker.

NHS Overpayment Response Pack

Letters to query the amount or agree a plan.

How to Read Your NHS Payslip

Check the months affected line by line.

NHS Payslip Checker

Compare what you were paid with what you should have been.

NHS Staff Representation Explained

Which unions can help you negotiate or dispute.

NHS Pay Calculator

Your normal take-home pay by band and point.

Frequently asked questions

Do I repay the gross or the net amount of an NHS overpayment? +
You should generally only be asked to repay the net amount you actually received. The figure on a payslip is gross, before Income Tax, National Insurance and pension, but only the net amount reached your bank account. Trusts usually recover the net figure when the overpayment is corrected within the same tax year, because payroll can correct the tax and National Insurance. If it is only found after the tax year has ended, a trust may need to recover the gross amount and correct your tax record separately. If a request looks higher than you received, ask for the calculation in writing before agreeing.
How do I work out how much I actually received? +
Take your take-home pay with the overpayment included and subtract your take-home pay without it. The calculator does that using your normal pay, your tax region, NHS Pension tier and any student loan. As an example, £1,000 gross overpaid on top of a £38,000 salary in England leaves about £642 net in the bank, because of £180 income tax, £80 National Insurance and £98 pension. Your payslips for the affected months show the exact deductions.
Do I have to pay back an NHS overpayment if it was payroll's mistake? +
Generally yes. Money paid by mistake is normally recoverable whoever made the mistake, and section 14 of the Employment Rights Act 1996 says the usual protection against deductions from wages does not apply to reimbursing an employer for an overpayment of wages. What you can usually influence is whether the figure is right, whether it is net, and how it is repaid. A narrow legal concept called change of position can sometimes reduce what is recoverable, but it is a high bar, so take advice from your union or a solicitor before relying on it.
Can the trust take the whole overpayment out of my next payslip? +
Acas says an employer should not deduct money from your wages without letting you know, should talk to you first and agree how it will be paid back, and should be flexible and fair, with a repayment plan, where the amount is large or covers a long period. Every trust has its own policy, and the ones reviewed for our guide commonly set a limit on how much can come off a single payslip without your agreement, but the exact limit differs, so ask payroll for the policy and for any deduction to be confirmed in writing.
What if the overpayment was in a previous tax year? +
Payroll can only correct tax and National Insurance within the current tax year. If the overpayment relates to an earlier year, a trust may ask for more than the net amount and your tax record is corrected separately. The checker shows your estimated net and the larger figure you could be asked for. Ask payroll in writing how the tax, National Insurance and pension for each earlier year are being dealt with and whether any of it comes back to you through HMRC, and ask HMRC or your union if the answer is unclear.
What if I have left the NHS and they are asking for money back? +
While you are employed recovery usually happens through a payroll deduction. After you leave there is no payroll to deduct from, so your former employer generally asks you to repay directly and, if you do not, can pursue it as an ordinary civil debt, for example through a court claim. Acas says that if a former worker refuses to pay back the money, the employer might make a court claim. You still have the normal rights of anyone facing a debt claim, including checking the amount, so ask for the calculation before agreeing anything.
How long can the NHS take to recover an overpayment? +
There is no single national answer. It depends on your trust's policy and on general limitation law, which in England and Wales is usually six years for simple contract and debt claims, though it can differ and Scotland is slightly different. A very long delay can itself be a fair point to raise if you are disputing recovery. If the overpayment is old, ask your union or a solicitor to check the time limit that applies to you.
How do I propose an affordable repayment plan? +
Write to payroll or HR with a specific monthly amount and say why. A simple method is to take your monthly take-home, subtract your essential outgoings and offer a share of what is left. For example, £2,400 repaid at £200 a month takes 12 months. Ask them to confirm any plan in writing with the monthly amount, start date and end date. It is your proposal, not an entitlement, and the trust decides whether to accept it under its own policy.
Is interest added to an NHS overpayment repayment plan? +
The schedule on this page adds no interest, because it shows the overpaid amount repaid in equal instalments. Whether your trust adds anything is set by its own policy and we have not verified a national rule, so ask payroll to confirm in writing that the total being recovered is the amount agreed and that nothing else is being added.
What if I dispute that I was overpaid at all? +
Ask for the full written calculation first, showing which pay periods, rates and hours it is based on, and check it against your payslips and contract. Some overpayments turn out to be an enhancement that was earned or a pay point change that was correctly backdated. If you still disagree, raise it in writing through your trust's overpayment or grievance procedure and involve your union. Disputing the amount and negotiating how to repay a figure you accept are different conversations, so be clear which one you are having.
What does the Overpayment Response Pack add to this free checker? +
This checker tells you the numbers: your estimated net, the range you could be asked for, and a repayment schedule. The Overpayment Response Pack is a separate paid product at £7.99 one-off with 90 days of access. It turns your figures into editable letters to ask for a written explanation, query or dispute the amount, ask to pause deductions or propose a plan, plus a call script. The checker stays free either way.