Your situation
Getting a refund after a wrong tax code
Independent site, not HMRC. Only HMRC can change your code: use your HMRC online account or app.
Two routes bring overpaid tax back: your own payroll once the corrected code arrives, or HMRC directly after the tax year ends.
Should come back to you
£1,048.40
In your September pay (month 6), if the new code reaches payroll by then.
| Tax on BR | £2,500.00 |
| Tax with 1257L over the same pays | £1,451.60 |
| Tax line on that payslip | −£758.00 |
Assumes no other pay earlier in the tax year. With a P45 from an earlier job, the refund depends on the tax already paid there.
Tax overpaid because of a wrong code usually comes back through your own pay, not by a separate payment. When HMRC updates the code, it checks whether it holds all your income details for the year; if it does, it asks your employer or pension provider to pay back the difference through your wages, normally when the new code is first used (GOV.UK). Monthly paid staff should see it on the next or the following pay, weekly paid staff on the third. Example: £2,500 a month taxed on BR from April to August pays £2,500.00 where 1257L would have taken £1,451.60, so £1,048.40 returns in the September payslip. If HMRC lacks some figures, the refund waits until after 5 April: a P800 letter arrives between June and March, and money claimed online is sent within 5 working days, a requested cheque within 6 weeks, and an automatic cheque within 14 days of the letter.
Overpaid tax and how it comes back
Overpaid
£714
| Tax due with 1257L | £3,486 |
| Refund online | 5 working days after claiming |
| Refund by cheque | within 6 weeks |
Employment income in England, Wales or Northern Ireland with the standard allowance.
Rules read on HMRC’s texts by Radif Partners · Editorial policy · Method
Route one: the refund inside your next pay
A cumulative code compares the tax due on everything you have earned since 6 April with the tax already taken. When the corrected code reaches payroll, that comparison is made with the right allowance, and any excess is handed back on the same payslip as negative tax. This is why GOV.UK describes the refund as something your employer or pension provider pays in your wages once HMRC has asked them to.
Two conditions apply. HMRC must have all your income details for the tax year, and your employer must have loaded the new code. Monthly payrolls should use it on the next or the following pay, weekly payrolls on the third pay. The table shows what comes back when a £2,500 monthly salary has been wrongly coded BR for a few months before 1257L arrives.
| BR from, for | Taken on BR | Due on 1257L | Comes back | In the pay of |
|---|---|---|---|---|
| April, 3 months | £1,500.00 | £871.00 | £629.00 | July |
| April, 6 months | £3,000.00 | £1,742.00 | £1,258.00 | October |
| August, 3 months | £1,500.00 | £32.40 | £1,467.60 | November |
| August, 6 months | £3,000.00 | £903.40 | £2,096.60 | February |
The emergency calculator at the top lets you change the wrong code, the months and the pay. The same arithmetic applies to an emergency code that has been replaced, only with a smaller gap.
When the payroll route is blocked
HMRC cannot repay what it cannot measure. If your record is missing a previous job, a pension or a benefit, no refund is made until those details arrive from the employer, pension provider or benefits office. After a change of job, the quickest way to unblock it is to give the P45 from the old job to the new employer, or to ask the old employer for one if it never came. The P45 guide explains which parts to hand over.
If you are not sure the code is wrong at all, first compare it with your situation in the HMRC online account and update what is missing. The wrong code checklist lists the usual mismatches.
Route two: the P800 after the tax year ends
When the year closes on 5 April without the refund being paid, HMRC collects the year's figures from employers, from pension providers and from the benefits office, checks what you paid and writes to you if the total is wrong (GOV.UK). These tax calculation letters are sent between June and March of the next tax year, and they say which way the money will come:
- claim online, by bank transfer: paid within 5 working days, using the reference on the letter and your National Insurance number;
- ask online for a cheque: sent within 6 weeks;
- personal tax account or HMRC app: available if you have a UK bank account;
- automatic cheque: when the letter says so, it arrives by post within 14 days of the letter's date, with no claim needed.
Overpaid tax and how it comes back
Overpaid
£714
| Tax due with 1257L | £3,486 |
| Refund online | 5 working days after claiming |
| Refund by cheque | within 6 weeks |
Employment income in England, Wales or Northern Ireland with the standard allowance.
Checking the amount you get back
Your P60 shows the tax taken by each employer over the year and is the document GOV.UK names as proof when claiming back overpaid tax. Add up the P60s, plus the P45 of any job you left during the year, compare the total with the tax due on your income, and the difference should match the refund. If a P800 uses amounts you believe are wrong, tell HMRC which figures are incorrect and what they should be; HMRC either sends a new calculation or explains why it disagrees.
Refunds for reasons other than a job or a pension, such as job expenses or a redundancy payment, follow their own routes, described in HMRC's refund checker. If the letter goes the other way and shows tax owed, the underpayment guide explains how it is collected.