A complete guide to the UK P45 form: what it is, what its three parts mean, emergency tax codes, how to claim a refund, and what to do if you lose yours.
A P45 is a form issued by your employer when you leave a job — whether through resignation, redundancy, retirement, or the end of a fixed-term contract. Formally titled "Details of employee leaving work," the P45 provides a record of everything that has happened with your pay and tax from the start of the tax year to the day you left employment.
The P45 is critical to ensure that you pay the correct amount of tax in any new job you take on. Without it, your new employer will not know how much of your personal allowance you have already used, or how much tax you have already paid — potentially leading to under or overpayment of tax.
P45s have been in use in the UK since the 1940s. While many payroll processes have been digitised, the P45 remains a legal requirement and a core document in the UK tax system.
A P45 has three parts, each serving a different purpose:
Your employer sends Part 1 directly to HMRC. It contains your details, tax code, National Insurance number, earnings, and tax paid. You never see this part. It updates HMRC's records so they know you have left the job.
Part 1A is your copy of the P45. Keep it for your records. It contains the same information as Part 1: your total gross pay, income tax paid, NI number, tax code, and leaving date. You may need it for tax refund claims or Universal Credit.
Parts 2 and 3 are given to your new employer. They use this information to apply your correct tax code from the start of your new employment. Giving these to your new employer promptly is important to avoid emergency tax.
In practice, many P45s are now issued electronically. If your employer uses a digital payroll system, you may receive your P45 as a PDF. The same three parts apply — Part 1 is transmitted to HMRC electronically, Part 1A is emailed or made available online for you, and Parts 2 and 3 are provided to you to hand to your new employer (or to share digitally).
Your employer is legally required to give you a P45 on or around the day you leave employment. In practice, this means:
If your employer has not given you your P45 within a reasonable time after leaving (typically a few weeks), you should contact your former employer's payroll department. If they still refuse or are unable to provide it, HMRC can help.
Here is a step-by-step guide for handling your P45 when starting a new job:
Part 1A is your personal copy. File it somewhere safe — either physically or as a digital scan. You may need it to check your tax code, claim a tax refund, or as proof of income/employment end date for Universal Credit.
Hand over Parts 2 and 3 to your new employer's HR or payroll team as soon as possible — ideally on your first day or even before you start. This allows them to set up your tax code correctly from the outset.
When you receive your first payslip from your new employer, check that the tax code shown matches what was on your P45. The most common code for someone using their full personal allowance is 1257L. If the code looks wrong, contact your new employer's payroll team immediately.
At the end of the tax year, check your P60 (from your new employer) to make sure your total tax for the year looks correct. If you changed jobs mid-year and there was a gap in employment, you may have overpaid tax and be entitled to a refund.
If you start a new job without providing a P45, or if your new employer has not yet received your P45 details, you will likely be placed on an emergency tax code. This is temporary — once HMRC and your employer have the correct information, your tax code is usually updated within a few weeks.
| Code | What It Means | Effect |
|---|---|---|
| 1257L W1 or 1257L M1 | Week 1 / Month 1 basis. Your personal allowance is divided by 52 or 12 and applied each period, without considering previous earnings. | You may overpay if most of your allowance was used in a previous job; you may underpay if you have earned less this year. |
| BR | Basic Rate — all earnings taxed at 20%. | Used when HMRC does not know if this is a second job. Can lead to significant overpayment if it is your only job. |
| 0T | Zero personal allowance — all earnings taxed at your marginal rate (20%, 40% or 45%). | Applied when no starter information is available. Often results in significant overpayment. |
| D0 | All earnings taxed at 40% (higher rate). | Used if HMRC believes this is a second or additional job where higher-rate tax applies. |
Emergency tax is not a penalty — it is a mechanism to ensure some tax is collected when full information is unavailable. Any overpaid emergency tax is eventually refunded, either through your payslip once the correct code is applied (cumulative adjustment) or via a P800 at year-end.
If you have left your job and need to apply for Universal Credit, your P45 is an important piece of supporting evidence. The Department for Work and Pensions (DWP) will want to verify your employment history and the date your employment ended.
When applying for Universal Credit:
If you leave a job part-way through the tax year and do not immediately start a new job, you may be entitled to a tax refund. This happens because the PAYE system assumes you will earn the same amount for the full year and deducts tax accordingly. If you stop working mid-year, the tax you have paid may be more than you owe for the year.
If you start a new job: Give your P45 to your new employer. The cumulative PAYE system will automatically account for the tax already paid, and your new employer's payroll will reduce your tax deductions accordingly.
If you do not start a new job and are claiming Jobseeker's Allowance (JSA) or other benefits: HMRC will generally reconcile your tax at year-end and send you a P800 if you have overpaid.
If you do not start a new job and are not claiming benefits: You can claim a refund directly from HMRC by calling 0300 200 3300 or by logging into your Personal Tax Account at GOV.UK. You will need your P45 details to hand.
Unlike a P60, your employer cannot issue a replacement P45. This is because the P45 is a legal document that forms part of the PAYE record — once issued, a replacement could create confusion or duplication in HMRC's systems.
If you have lost your P45, the solution is straightforward:
The Starter Checklist replaced the old P46 form. It is a simple document you complete for your new employer if you do not have a P45 to hand. Your new employer uses your answers to determine the right tax code to apply.
The Starter Checklist asks you to tick one of three statements:
Completing the Starter Checklist accurately is important. If you tick the wrong statement, you may pay too much or too little tax. The checklist is available on GOV.UK and your new employer should provide one when you join without a P45.
Being made redundant and receiving a P45 can happen at the same time, and it is important to understand how redundancy pay is treated on your P45.
The first £30,000 of a genuine redundancy payment is tax-free. This means it should not appear on your P45 as taxable earnings. Your P45 will show your normal salary earnings up to your leaving date, but statutory redundancy pay (up to the £30,000 threshold) is excluded from the PAYE earnings figure.
Any redundancy pay in excess of £30,000 is taxable and will be included in your P45 earnings. Your employer should deduct income tax on this excess through PAYE before your final pay is issued.
Pay in lieu of notice (PILON) is always taxable and subject to NI, and will appear on your P45 as part of your earnings regardless of how it is structured. This changed under April 2018 rules — post-employment notice pay (PENP) is always taxable.
The P45 and P60 are often confused. Here is a clear comparison:
Read our full P60 Explained guide for complete details on the end-of-year certificate.
A P45 is a form issued by your employer when you leave a job. It shows your total earnings and income tax paid from 6 April to your leaving date. It has three parts: Part 1 goes to HMRC, Part 1A is your copy, and Parts 2 and 3 go to your new employer. It is used to ensure you pay the correct amount of tax in your next job.
Give Parts 2 and 3 of your P45 to your new employer as soon as possible — ideally on or before your first day. This allows them to apply your correct tax code from the start, preventing emergency tax. Keep Part 1A for your own records.
Without a P45, you will be placed on an emergency tax code. The most common is 1257L W1/M1, which applies your personal allowance on a non-cumulative basis each pay period. This may result in overpayment of tax. To minimise this, complete a Starter Checklist for your new employer as soon as possible.
No. Unlike a P60, your employer cannot issue a replacement P45 once the original has been issued. If you have lost your P45, complete a Starter Checklist for your new employer. For other purposes (such as tax refund claims), your Personal Tax Account on GOV.UK holds the same earnings and tax data.
Yes. If you left a job part-way through the tax year and did not start another immediately, you may have overpaid tax because you did not use your full annual personal allowance. Contact HMRC (0300 200 3300) or use your GOV.UK Personal Tax Account to check and claim any refund. HMRC may also send you a P800 automatically at year-end.
The Starter Checklist is a form completed when you start a new job without a P45. You choose one of three statements about your employment history since 6 April. Your new employer uses your answer to apply a provisional tax code. Statement A (first job since April) gives you code 1257L; Statement B (only job, but had previous employment this year) gives 1257L W1/M1; Statement C (second job) gives BR.
Your P45 shows your regular salary earnings up to your leaving date. Statutory redundancy pay up to £30,000 is tax-free and does not appear as taxable earnings on your P45. Any redundancy pay above £30,000 is taxable and is included. Pay in lieu of notice (PILON) is always taxable and included in your P45 earnings figure.