Decode your UK tax code — find out what it means, what Personal Allowance it gives you, and whether it looks correct.
Find your tax code on your payslip, P60, or P45.
Enter your tax code
Find your tax code on your most recent payslip, P60, or P45. It is usually a 4-digit number followed by a letter, such as 1257L.
See the full explanation
The checker decodes your code, shows your effective Personal Allowance, and explains why you might have this code.
Check if it looks right
If your circumstances suggest a different code, the checker flags potential issues and links to HMRC contact details.
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Disclaimer: All results are estimates for guidance only and do not constitute financial, tax or legal advice. Always consult a qualified professional.