How much tax have you actually overpaid?
Millions of UK workers overpay HMRC every year through incorrect PAYE tax codes, unclaimed employment expense deductions, and missed self-assessment filing opportunities. Most never check. Enter your details below and see where you stand.
Your quick tax estimate
Your estimated breakdown for 2025/26
The most common reasons workers overpay
Wrong tax code
An emergency code (e.g. 1257L W1/M1) taxes you at a flat rate with no cumulative adjustment. Very common after a job change.
Work from home allowance
If your employer doesn’t reimburse home office costs, you can claim up to £6/week directly from HMRC — backdated 4 years.
Uniform & equipment
Tools, uniform maintenance, and professional subscriptions are all potentially deductible — but most workers never claim them.
Mileage underclaimed
If you drive for work and your employer pays less than 45p/mile, you can claim the difference as a tax deduction from HMRC.
There are legal ways to pay less
You don’t need an accountant to claim back what HMRC owes you. See the three most effective income tax reduction strategies — used by over 2 million UK workers to recover overpaid tax and reduce their self-assessment liability.
Show me how to reduce my tax bill →This calculator provides estimates only and is not tax advice. Figures are based on standard 2025/26 HMRC tax rates and thresholds. Individual results will vary. Links marked as sponsored may earn referral fees. Always verify your tax position directly with HMRC or a qualified tax adviser. All financial providers listed are FCA-regulated.