What is a P45?

Wollit Team2 minute read · Updated 28th July 2024

A P45 is a tax form that your employer must give you when you leave a job in the UK. In it, you’ll find information about your income and tax for that tax year up until your last day of employment.

The P45 is really important when starting a new job, as it helps your new employer put you on the correct tax code and deduct the correct amount of tax from your wages for the rest of the tax year.

What information is on a P45?

A P45 includes things like:

Your name and address.
Your National Insurance number.
The date you stopped working for your employer.
Your total taxable wage so far in the tax year.
The total tax you've paid so far in the tax year.
Your tax code.

When do I get a P45?

Your employer must give you a P45 when your employment ends, regardless of reason.

It doesn’t matter if you’re moving to a new job, retire, get fired, or take a sabbatical. If you stop working for them, you need a P45.

If you don't receive your P45, you should ask your employer for it. By law, they must give it to you.

What if I don't have a P45?

If you don't have a P45 when starting a new job, your new employer will need to work out your tax code and how much tax to deduct from your salary. You'll need to provide information about any other jobs you have, benefits you receive, and any student loans.

Your new employer will then use this information to calculate your tax code before your first payday. They may ask you to fill in a “starter checklist” form to get this information.

Why is a P45 important?

A P45 is important for a few reasons:

It ensures your new employer deducts the correct amount of tax from your salary. Without it, you could end up paying too much tax, at least at the beginning.
You need it to claim certain benefits if you become unemployed, such as Job Seeker’s Allowance.
You also need it to claim tax refunds if you've overpaid tax.
You may even need it in the future if you want to check your tax history, for example when withdrawing money from a pension.

Do I need a P45 when going through a credit check?

No, you don’t need a P45 when going through a credit check, as it's a tax form rather than a credit-related document.

However, you might need a P45 when applying for loans or mortgages. Lenders will need to look at more than just your credit history when deciding on your application.

They’ll need to understand your income as well – and this is where a simple document like a P45 comes in very handy.

Having a P45 can also help you give lenders more information about your income during the pre-approval process. This could save you from having a loan application denied – which can then lower your credit score since you went through a hard check for nothing.

If you want to understand your loan approval chances, try to use an eligibility tool first. You should also keep working on your credit score – for example, by downloading a credit-building app like Wollit.

Wollit works by reporting a fixed fee monthly subscription as a loan repayment to the credit reference agencies (Experian, Equifax, and TransUnion). This helps you build or rebuild your credit history by showing that you can pay debt on time. It can even report your monthly rent payment to Experian, adding another line in your credit report that shows lenders you're responsible and pay your bills when they’re due. In time, this will help you improve your credit score so you won’t need to be worried about any credit check ever again.