A P45 is a document your employer gives you when you leave a job. It shows how much you've earned and how much Income Tax you've paid during the tax year, helping HMRC and your new employer apply the correct tax code and avoid overpaying or underpaying tax.
Changing jobs is exciting, but it often comes with paperwork that many people overlook. One of the most important documents you'll receive when leaving employment is your P45. Although it may seem like just another form, it plays a crucial role in ensuring your tax records remain accurate and that your next employer pays you correctly from your very first payday.
Whether you've resigned, been made redundant, or are starting a new career, understanding what a P45 is can save you from emergency tax codes, unexpected deductions, and unnecessary delays when dealing with HMRC.
In this guide, we'll explain exactly what is a P45, how to get a P45, why it matters, when you'll receive one, and what to do if it goes missing.
A P45 is an official document issued by an employer when an employee leaves their job. It summarises your earnings and the Income Tax you've paid from the beginning of the current tax year until your leaving date.
The information on your P45 allows your new employer or pension provider to continue deducting the correct amount of tax without starting your tax calculations from scratch.
A P45 is not something you need to request in most cases. Employers are responsible for providing it once your employment officially ends and your final payroll has been processed.
Although the layout is standardised, your P45 contains several important details, including:
These figures are essential because they provide a complete picture of your tax position up to the date you left your previous employment.
You should receive your P45 shortly after your final salary has been processed. Some employers issue it on your last working day, while others send it after the final payroll run.
The document may be provided:
If you haven't received your P45 within a reasonable timeframe, it's worth contacting your former employer's payroll department.
You don't need to apply for or request a P45 in most cases. Your employer is legally responsible for issuing it when your employment ends and your final salary has been processed through PAYE.
Here's how you can get your P45:
Leave your job: Once you resign, retire, are made redundant, or your employment ends, your employer will prepare your final payroll.
Receive your P45: After your final pay has been processed, your employer will provide your P45. It may be given to you as a paper document, sent by post, or made available electronically through your company's payroll or employee portal.
Check the details: Ensure your name, National Insurance number, tax code, earnings, and Income Tax deducted are correct before passing it to your new employer.
Many people underestimate the importance of this document, but it can directly affect how much tax you pay.
Without a P45, your new employer may have limited information about your previous earnings. This can result in you being placed on a temporary or emergency tax code until HMRC updates your records.
Your P45 carries forward your tax position for the current tax year. This reduces the likelihood of paying more Income Tax than necessary.
If you're claiming certain state benefits or starting to receive a workplace or private pension, your P45 helps ensure your tax details are accurate.
The information submitted by your employer allows HMRC to maintain accurate employment and tax records throughout the year.
Not everyone starts a new job with a P45.
You may not have one if:
In these situations, your new employer will usually ask you to complete a Starter Checklist. This allows them to estimate the correct tax code until HMRC provides updated information.
Although you can still start work without a P45, providing one is generally the quickest way to ensure your tax deductions are accurate.
No. Once a P45 has been issued, employers cannot produce a duplicate.
If you've misplaced it, don't panic. Your previous employer may be able to provide a statement showing your final pay and tax details, although it won't be an official replacement.
Alternatively, HMRC already holds your employment information through the PAYE system, and your new employer can obtain updated tax information electronically.
Once you receive your P45:
It's a good idea to keep employment records for several years, particularly if you need to resolve tax queries or apply for mortgages, loans, or benefits.
A P45 is much more than an exit document, it ensures your tax records move with you when you change jobs. By providing accurate information about your earnings and Income Tax paid, it helps your new employer apply the correct tax code and reduces the risk of emergency taxation.
If you're unsure whether your P45 details are correct, have questions about PAYE, or need expert support with payroll, tax, or employment-related accounting, the experienced team at PHS Associates can help. We provide practical advice for employees, contractors, and businesses across the UK, helping you stay compliant and avoid costly tax mistakes. Contact us today for professional guidance to your circumstances.
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