P45 Explained UK
Understand your UK P45 form, decode your tax code, and know exactly what to do with it when changing jobs, claiming benefits, or retiring.
Plan Your P45 Next Steps
Select your current situation below. The planner will generate a personalised, step-by-step guide on exactly what to do with your P45 to avoid emergency tax and stay compliant.
P45 Action Planner
Get tailored guidance based on your employment status
P45 Quick Facts
Essential insights into UK employment tax documents
Understanding the P45 Process
Leaving a job involves a few administrative steps to ensure your tax record stays accurate. Here is how the P45 lifecycle works.
Your Final Payroll Run
When you leave, your employer calculates your total pay and tax for the tax year (6 April to 5 April) up to your leaving date.
Employer Submits Part 1 to HMRC
Your employer sends the first part of the P45 data directly to HMRC to update your national tax record, ensuring you are not over-taxed.
You Receive the Remaining Parts
You are given the remaining sections. You must hand Parts 2 and 3 to your new employer or Jobcentre Plus, and keep Part 1A for your own records.
New Employer Updates Your Code
Your new employer uses the information to apply the correct tax code, ensuring you continue to receive your correct tax-free personal allowance.
P45 Parts & Tax Codes
A handy cheat sheet for understanding the sections of a P45 and common tax codes you might see.
| P45 Part / Code | Who Keeps It? | Purpose / Meaning |
|---|---|---|
| Part 1 | HMRC (sent by employer) | Notifies HMRC of your leaving date, final pay, and tax paid. |
| Part 1A | You (the employee) | For your personal records. Keep it for mortgage, loan, or tax enquiries. |
| Part 2 | New Employer / Jobcentre | Used to set up your correct tax code or process your benefit claim. |
| Part 3 | New Employer / Jobcentre | Retained by the new employer or Jobcentre for their statutory records. |
| 1257L | N/A (Tax Code) | Standard tax code. You get a £12,570 tax-free personal allowance. |
| 1257L W1 / M1 | N/A (Tax Code) | “Week 1 / Month 1” emergency code. Tax is calculated only on current pay, ignoring previous earnings. |
| BR | N/A (Tax Code) | Basic Rate. All income from this job is taxed at 20% with no tax-free allowance applied. |
P45 FAQ
Answers to the most frequently asked questions about P45 forms, tax codes, and HMRC rules in the UK.
A P45 is a statutory tax document that your employer must give you when you leave a job. It details your tax code, total earnings, and the amount of tax you have paid in the current tax year.
Your employer should give you your P45 on your last day of work, or shortly after your final payroll run. If you do not receive it within a month, you should contact your former employer’s payroll department.
Employers cannot issue a replacement P45 form as it is a controlled HMRC document. However, you can ask your former employer for a ‘statement of earnings’ showing your tax code and pay to date. Alternatively, you can view your up-to-date tax record by logging into your HMRC Personal Tax Account.
No, a P45 does not expire. It is a historical record of your employment and tax paid for that specific tax year. You should keep Part 1A for your own records indefinitely, as it may be required for mortgage applications, student finance, or future tax enquiries.