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If you’ve ever looked at your tax bill and wondered if you’ve paid too much, you’re not alone. Many people find themselves in a situation where they owe less tax than what has already been paid—sometimes because of a wrong tax code, a reduction in income, or overlooked tax reliefs. The good news is that you can usually claim an overpayment from HMRC.
Why Do Overpayments Happen?
Tax overpayments occur for various reasons. You might change jobs partway through the year and not use your full personal allowance. Your employer could be using the wrong tax code. You might also incur expenses that qualify for tax relief, which you didn’t claim at the time. If your income falls suddenly—for example, you stop freelancing, or you don’t earn as much as you expected—you could end up paying more than necessary through Self Assessment payments on account. All these circumstances can leave you with an unexpected tax refund waiting in HMRC’s system.
Claiming a Refund If You’re an Employee
If you work as an employee, the most common reason for overpayment is an incorrect tax code or missing tax relief on allowable expenses. These might include job-related costs such as uniforms, tools, or travel for business (not commuting).
How to Make a Claim
- Check Your P800 Letter: HMRC often sends a tax calculation letter, known as a P800, to let you know you’ve overpaid. If your letter says you can claim online, visit the Gov.uk page at www.gov.uk/tax-overpayments-and-underpayments/if-youre-due-a-refund
- Enter your P800 reference number and National Insurance number. After completing the online claim, your refund should arrive in your bank account within five days.
- Use Form P87: If you need to claim tax relief on job expenses, like travel or professional subscriptions, fill out Form P87. You can submit it online or by mail, along with proof of your expenses (receipts, invoices, etc.). Including all necessary documents helps speed up the process.
- Personal Tax Account or App: Another option is to log into your personal tax account on Gov.uk or use the HMRC app. You can request your refund from there. If your P800 states that a check (cheque) is on its way, you don’t need to take any further action—just wait for it to arrive, usually within 14 days of the date on the letter.
Claiming a Refund If You’re Self-Employed
Being self-employed under Self Assessment can lead to overpayments if your income drops and your payments on account are set too high. You might also claim a loss that brings your taxable profits down, resulting in a refund.
How to Get Your Money Back
- Request Through Your Return: If you submit your Self-assessment tax return and spot an overpayment, you can select the option to request a refund directly on the return. HMRC usually processes these refunds automatically within about two weeks.
- Online Self-Assessment Account: If you didn’t choose to request a refund on your original return, you can still claim later through your online Self-Assessment account by clicking “Request a Repayment.”
- Personal or Business Tax Account: You can also use your personal tax account or your business tax account (if you’re operating as a sole trader) to claim a refund. HMRC lets you pick whether you want the money to land in your UK bank account or be sent by check.
Once your claim is in, HMRC generally processes the refund within two weeks. If you don’t see your money by then, consider contacting them to check on your claim’s status.
When to Expect Your P800
HMRC typically issues a P800 for each tax year if they find you’ve overpaid or underpaid. For 2023/24, most P800s should be sent out by the end of March. Keep an eye on your mailbox or your online account around this time. If you believe you’ve overpaid but haven’t received anything, you can still contact HMRC or check your personal tax account to see if a calculation is in progress.
How We Can Assist
At Tax Accountant, we believe no one should wait long for their rightful refunds. Our experts help identify overpayments, prepare accurate documentation, and submit claims to reduce delays. We’ll double-check your P800 calculations and guide you through self-assessment refunds to ensure a smooth process. Contact us today to start reclaiming what’s yours!