How to check your tax code
A tax code controls how tax is collected through payroll. A code different from 1257L can be correct; check the underlying calculation before assuming overpayment.
Where can I see the calculation?
Compare your payslip with HMRC’s Personal Tax Account. Look at allowances, benefits, other jobs, pension income and adjustments.
What do BR and emergency codes mean?
BR generally taxes the source at basic rate without an allowance. Emergency markers affect how payroll calculates tax. They are reasons to check, not proof that a refund is due.
How do I correct wrong details?
Update HMRC’s records through the official account or contact HMRC. Your employer normally follows the code HMRC supplies.
Before you claim
Keep records, subtract reimbursements and check what you have already claimed. Entitlement depends on your circumstances in each tax year. You can use HMRC’s services yourself without buying a report.