UK tax refund calculator - online

How does the UK tax refund calculator work?

The UK tax refund calculator lets you send the details needed for an estimate in 4 steps. After you complete the form, our specialists will review your tax situation and prepare a free HMRC (His Majesty's Revenue and Customs) refund estimate within 24 hours.

The calculator is free and comes with no obligation. Once you receive the estimate, you decide whether you want us to handle your UK tax return.

What should you prepare before using the calculator?

In the UK tax system, the key documents are those confirming your employment and the Income Tax paid:

• P60 - your annual summary of earnings and tax from your employer. You receive it after the end of the tax year, after 5 April
• P45 - a document issued when you leave a job, showing your earnings and tax paid with that employer
• Payslip - if you do not have a P60 or P45, the last payslip from the relevant tax year is enough

If you do not have any of these documents, you can still complete the calculator. We will help you obtain the necessary details from HMRC.

Why do people in England overpay tax?

The most common reasons for tax overpayment in the UK are:

• Emergency tax code - your employer assigns a temporary tax code, such as 0T or BR, so tax is deducted at a higher rate. This often affects people starting work in the UK
• Working for only part of the year - if you worked in England for just a few months, your Personal Allowance was not fully used
• Working for several employers - when you change jobs during the tax year, tax is often calculated using an incorrect tax code
• Construction Industry Scheme (CIS) - construction workers have tax deducted at source, which can often exceed the actual tax due

The UK tax year - how is it counted?

The UK tax year runs from 6 April to 5 April of the following year. That is why tax years are written as two years:

• Tax year 2025/2026 - from 6 April 2025 to 5 April 2026
• Tax year 2024/2025 - from 6 April 2024 to 5 April 2025

A UK tax return can be submitted up to 5 years back, which means you can select tax years as far back as 2021/2022 in the calculator.

What happens after you send the calculation?

After you submit the form, our team reviews your documents and prepares an estimate. If you decide to proceed, we handle the whole process: preparing the refund claim, contacting HMRC on your behalf and translating correspondence from the UK tax office. The usual waiting time for an HMRC refund is 6-12 weeks from submitting the claim.

The service is handled for a fixed fee, with no commission on the refund amount, so the recovered tax goes to you. You can find the details on the pricing page.

Why use the FenixTax calculator?

• Free calculation and estimate, with no obligation
• Reply within 24 hours
• Over 20 years of experience with foreign tax settlements
• Fixed fee, with no commission on your refund
• Contact with HMRC and correspondence translation on your behalf
• A network of over 140 service points across Poland