How do I know if HMRC owes me a tax refund?

HMRC may owe you a refund if you paid tax on an emergency code, only worked part of the tax year, have unclaimed work expenses, or qualify for Marriage Allowance. HMRC sends a P800 notice after the year ends if they calculate you've overpaid, but you can also claim proactively via your Personal Tax Account.

How far back can I claim a tax refund from HMRC?

You can claim a tax refund for overpaid tax going back 4 complete tax years. In the 2025/26 tax year, you can claim back to 2021/22. Claims for 2021/22 must be submitted before 5 April 2026.

Can I claim tax relief on working from home?

Yes. If your employer requires you to work from home, you can claim the HMRC flat rate of £6 per week (£312/year) without needing receipts. This gives basic rate taxpayers £62.40 back and higher rate taxpayers £124.80 back per year.

How much is mileage tax relief worth?

If you use your own car for work (not commuting) and are not fully reimbursed, you can claim Mileage Allowance Relief at 45p/mile for the first 10,000 miles and 25p/mile above that. At 45p/mile with no reimbursement, a basic rate taxpayer saves 9p/mile in tax.

Benefits & Tax

Tax Refund Calculator UK 2026 – Find Out If HMRC Owes You Money

Calculate whether HMRC owes you a tax refund and exactly how much. Covers overpaid PAYE, emergency tax codes, and detailed work expense categories — uniform allowances, mileage, tools, professional fees, working from home, and more.

Updated April 2026 · 2025/26 HMRC rates & flat-rate allowances

✅ Rates verified April 2026 · Sourced from HMRC, DWP & UK legislation · About our verification process

HMRC Flat-Rate Work Expense Allowances 2026

If your employer hasn't reimbursed you for work expenses, you can claim tax relief directly from HMRC. For many categories, HMRC has agreed flat-rate deductions that don't require receipts — you simply claim and HMRC reduces your taxable income by the agreed amount, giving you back 20% or 40% of the allowance depending on your tax band.

Expense type	Flat rate (per year)	Tax relief at 20%	Tax relief at 40%
Working from home (£6/week)	£312	£62.40	£124.80
Uniform / protective clothing (typical)	£60–£185	£12–£37	£24–£74
Tools & equipment (typical)	£60–£140	£12–£28	£24–£56
Mileage (first 10,000 miles)	45p/mile	9p/mile	18p/mile
Professional subscriptions (e.g. CIPD, NMC)	Actual cost	20% of cost	40% of cost
Early/late meal allowance	£5–£15/day	£1–£3/day	£2–£6/day

You have 4 years to claim. You can claim a tax refund for overpaid tax going back 4 tax years. That means in the 2025/26 tax year you can still claim for 2021/22, 2022/23, 2023/24, and 2024/25. Claims for 2021/22 must be made before 5 April 2026.

Mileage Allowance Relief

If you use your own car for work (not commuting) and your employer pays you less than the HMRC approved amount, you can claim Mileage Allowance Relief on the difference. The approved rates are 45p/mile for the first 10,000 miles and 25p/mile thereafter. If your employer pays nothing, you can claim the full 45p/mile on up to 10,000 miles — that's £4,500 of tax-deductible expense, giving a basic rate taxpayer £900 back.

Working From Home Relief

You can claim the £6/week flat rate (£312/year) if your employer requires you to work from home — either because there is no office available or your role requires it. You don't need receipts. The relief is worth £62.40/year at basic rate and £124.80/year at higher rate. You cannot claim if you work from home by personal choice when an office is available.

How to claim: Most expense claims are made via your HMRC Personal Tax Account at gov.uk/claim-tax-relief-for-your-job-expenses. You can also write to HMRC or submit a Self Assessment tax return if you have one. Refunds are usually paid within 5 working days to a bank account.