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The short answer
If you leave a UK job before 5 April and earn little or nothing for the rest of the tax year, you have usually paid too much tax, because PAYE spreads your £12,570 Personal Allowance across the whole year. Start a new job and the overpayment normally comes back through your new employer's payroll once they have your P45; stop working and HMRC can repay after the year ends with a P800 letter, sent between June and March, or you can claim sooner using GOV.UK's refund checker.
Many Nigerians leave their first UK job within a year or so. A care contract ends, a sponsor changes, a student finishes a placement, or a better offer arrives. Each time, the same question follows the final payslip: was too much tax taken, and how do you get it back? The answer depends on one form, the P45, and on what you do for the rest of the tax year, which runs from 6 April to the following 5 April.
Why leaving mid-year often means a refund
PAYE works cumulatively. On the usual 1257L code, your employer gives you one twelfth of the £12,570 Personal Allowance each month and taxes the rest. The system assumes you will keep earning at the same rate all year. If you stop in October and earn nothing more, you have only used half of your allowance against your pay, so the tax taken was worked out as though more income was coming.
Worked example (illustrative, Income Tax only)
Example: Ada earns £2,500 a month from April to September, £15,000 in total, on code 1257L. By September PAYE has given her six months of allowance (6 × £1,047.50 = £6,285) and taxed £8,715 at 20%, which is £1,743. Over the full tax year her income is £15,000, so her real liability is 20% of £2,430 (£15,000 minus £12,570), which is £486. If she earns nothing else before 5 April, she has overpaid £1,257 (£1,743 minus £486).
The opposite can also happen. GOV.UK lists leaving one job, starting another and being paid by both in the same month among the reasons people end up with a tax calculation letter, which can show tax owed as well as tax repaid.
Your P45: what it is and what to do with it
GOV.UK says your employer should give you a P45 when you leave. It shows your leaving date, the pay you received and tax deducted from 6 April to that date, your tax code and your National Insurance number. If it is on paper:
- Give Parts 2 and 3 to your next employer.
- Keep Part 1a for your own records.
- If you lose it, you cannot get a replacement. Your new employer will ask you to complete a starter checklist instead.
- Your pay and tax for the last five tax years can be seen in your HMRC personal tax account or the HMRC app, which helps if the P45 never arrives.
Without a P45, a new employer may put you on an emergency code, ending W1, M1 or X, until HMRC updates it. GOV.UK says HMRC can take up to 35 days from the start of a job to update a code. See emergency tax codes in a first UK job and what 1257L means.
Three situations, three routes
| After leaving you… | How the overpayment usually comes back |
|---|---|
| Start another job in the same tax year | Through your new employer's payroll once they have your P45 or the right code; GOV.UK says an overpayment can be refunded through your pay |
| Stop working and stay in the UK | HMRC reviews the year after 5 April and may send a P800 tax calculation letter, sent between June and March of the following tax year; or you claim earlier through GOV.UK |
| Leave the UK | A separate route, form P85, unless you file a Self Assessment return for that year |
If you start a new job
Hand over the P45 on day one. Your new employer uses the year-to-date pay and tax figures on it, so the next payslips catch up on the allowance you did not use. Check the code on your first two or three payslips. GOV.UK says a new code is sent to you and your employer within 15 working days of a change, and monthly paid staff usually see it on the next or following payslip.
If you stop working and stay
You can wait for the end of the tax year. If HMRC finds an overpayment it sends a tax calculation letter, also called a P800. You need the P800 reference and your National Insurance number to claim. GOV.UK says money claimed through the online bank transfer service is sent within 5 working days; if you ask for a cheque, allow 6 weeks; and if the letter says a cheque is coming, it should arrive within 14 days of the letter's date.
If you do not want to wait, use GOV.UK's "Check how to claim a tax refund" tool. It covers refunds on pay from a job and on UK income earned before leaving the UK. GOV.UK states that you cannot claim through the tool itself: it points you to the correct service or form for your case.
If you are leaving the UK
The P85 is for people who lived and worked in the UK and want tax back when they go. You need your P45 for it. It is not needed if you file a Self Assessment return for the year you leave. Our guide to tax when returning to Nigeria covers it, including keeping a UK account open for the repayment.
What to check first
- That you have a P45 from the job you left, or can see the leaving figures in your personal tax account.
- That the leaving date, pay and tax on it match your last payslip.
- Whether you will work again before 5 April. That decides which route above applies.
- That your address and bank details are current in your HMRC account, so a P800 or repayment reaches you.
- That any refund message is genuine before you click anything.
Where Pryme fits
A refund arrives in pounds and can stay in pounds. A Pryme Personal Account holds GBP with its own local account details alongside NGN, USD and EUR (multicurrency), and if you decide to send some home, Swap shows the rate and the fee before you approve. Outside Nigeria, Pryme's activities are carried out through regulated partners.
Questions people ask
Will HMRC refund my tax automatically after I leave my job?
Often, yes. If you start another job, the refund usually comes through the new payroll. If you stop working, HMRC reviews the year after 5 April and may send a P800 letter between June and March of the following tax year.
How long does a UK tax refund take?
For a P800 refund claimed online by bank transfer, GOV.UK says 5 working days. A cheque you ask for takes about 6 weeks; one the letter says is coming should arrive within 14 days of the letter's date.
I lost my P45, can I get another one?
No. GOV.UK says a P45 cannot be replaced. Your new employer uses a starter checklist, and your past pay and tax are visible in your HMRC personal tax account or the HMRC app.
Can I claim a UK tax refund before the end of the tax year?
Yes, in some cases. GOV.UK's refund checker covers refunds on pay from a job and points you to the right claim route; it does not take the claim itself.
Sources
- GOV.UK: PAYE forms P45, P60 and P11D, P45 (updated 30 Sep 2026) · accessed Oct 2026
- GOV.UK: Tax overpayments and underpayments (updated 20 Oct 2026) · accessed Oct 2026
- GOV.UK: If your tax calculation letter (P800) says you're due a refund · accessed Oct 2026
- GOV.UK: Check how to claim a tax refund (updated 2 Oct 2026) · accessed Oct 2026
- GOV.UK: Tax codes · accessed Oct 2026
- GOV.UK: Report HMRC phishing emails, texts and phone call scams (updated 24 Nov 2025) · accessed Oct 2026
This article is general information, not financial, legal or tax advice. Products described are provided under the terms on this site and are subject to regulation and eligibility.