UK Tax Back Calculator

Calculate Your Leaving UK Tax Back Easily

Leaving the UK can mean you overpay tax and be owed tax back from HMRC.

The leaving the UK tax back calculator can be used by both overseas workers and UK expats to get an estimate of what you might be owed.

When departing the UK the most common reason for being due a tax refund is not using your full tax-free allowance in that tax year.

The calculator will estimate whether HMRC owes you money based on the tax you’ve paid versus the basic tax free personal allowance in that year.

It’s completely free and doesn’t store any of your personal information, helping you review your position before you decide to make a formal claim.

Depending on your circumstances you might be owed a UK tax refund for reasons other than your personal allowance.

We explain below different scenarios why you might get a tax refund from the UK, what forms you need to fill out, and how to get the most money back from your tax back claim.

What do I need to use the UK tax back calculator?

To use the tax back calculator you need your final P45, final payslsip or P60 from your last employer in the UK.

Your final P45, final payslip or P60 will normally show all of your income and tax paid in the tax year you leave.

If you don’t have the information you should be able to access the same information by using the HMRC personal tax account service online.

What else can I claim a UK tax refund for?

It’s really important to know what else you can claim tax back for. You could be owed more than you think but HMRC expects you to submit a claim to access your refund.

You can make a claim for the following at the same time as making a leaving the UK tax refund claim:

• Employment expenses linked to your PAYE income.
• Paying tax on a UK pension when you’re not living in the UK.
• Paying tax on rental income when you’re not living in the UK.

This is not an exhaustive list with our free income tax guides here to highlight other areas of tax that may be relevant to you.

Is there a timescale to claiming tax back?

Tax can be reclaimed for the last four years only, so it’s worth checking for as far back as you can go.

Because of the tax deadline trying to make a claim as soon as you can is always recommended to ensure you don’t lost out on money you are owed.

Other timescales can apply if you are claiming for capital allowances or for overpaid national insurance contributions.

Can I still claim if I have already left the UK?

If you’ve already left without submitting your tax rebate claim, don’t worry—it’s not too late.

You can still reclaim overpaid taxes by completing form P85 online, which is often faster than postal applications.

HMRC might request additional details about your overseas work and living situation.

How do I claim my UK tax back?

You can normally do it yourself by using HMRC’s free online service.

Making a UK tax back claim as quickly as you can is recommended to avoid missing the PAYE or self assessment deadlines.

If you do not have to complete a self assessment tax return for the year in which you leave the UK you should complete a form P85.

This is the official HMRC form for people who are leaving the UK and is used to update your record with your change in circumstances.

Form P85 leaving the UK

The P85 form can be completed and submitted online directly to HMRC using the government gateway.

You can also complete the P85 on screen, print it off and then post it to HMRC to the address provided on the form.

The P85 can be submitted at the point of leaving the UK meaning you don’t need to wait until the tax year ends to make your claim.

Self Assessment tax return when leaving the UK

A P85 should not be needed if you have to complete a self assessment tax return for the year in which you leave the UK.

Your self assessment tax return for the year in which you leave can only be submitted after the tax year ends.

This means if you leave the UK before the tax year ends you will need to wait until after the 5th April to submit your tax return.

If you are due a leaving the UK tax refund this will be repaid to you (usually by BACS to your UK bank account) by HMRC after your tax return has been processed.

Leaving the UK tax refund P800 tax calculation

HMRC will post you a form P800 tax calculation after they have processed your P85 to confirm how much tax back you are entitled to.

Your P800 tax calculation will give you a breakdown of how HMRC calculated your tax refund.

You should check your P800 carefully to make sure the figures used are accurate.

If you feel that something may not be correct you should call HMRC on the phone number shown on your P800 or make contact via their webchat service.

Leaving the UK Tax Refund Frequently Answered Questions:

Is the calculator result guaranteed to be accurate?

Our calculator only provides estimates based on standard tax calculations, but the final refund amount may vary depending on your complete tax situation.

We recommend using the estimate as a guide to determine whether it’s worth pursuing a formal claim with HMRC.

Do I need to pay anything to use the calculator or claim my refund?

No, both the calculator and the official HMRC refund process are completely free.

You can calculate and claim yourself using our free tool and HMRC’s own services.

What if I disagree with HMRC’s calculation?

If you receive a reply from HMRC that you disagree with you check it carefully against your records.

If you believe there’s an error, contact HMRC directly to discuss the discrepancy. Keep all your employment documents as evidence to support your case.

Can I use this if I’m self-employed?

The calculator is primarily designed for employed individuals with P45 or P60 documents.

If you’re self-employed, your tax situation is more complex and managed through the self-assessment system.

Not leaving the UK? We have other calculators for you too – calculate your Tax Back.

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