Donaldson R F UK Tax Code Decoder
Enter a PAYE tax code to see what it means — the tax-free amount, any Scottish or Welsh prefix, and emergency or K-code markers.
How tax codes work
HMRC starts from your Personal Allowance (£12,570 for 2026/27) and subtracts any untaxed income or deductions, such as company benefits. The number left shows your tax-free amount, divided by 10 with the last digit dropped: a code of 1257L means £12,570 is tax-free. A letter follows to show the type of allowance.
A code starting with S means Scottish rates apply, and one starting with C means Welsh rates apply. A code ending in a space and W1, M1 or X is an emergency code, worked out on that single pay period as if it applied for a whole year. A code starting with K means your deductions are bigger than your allowance — the number after K is the extra amount (×10) added to your taxable pay, not subtracted from it.
Source: GOV.UK: What your tax code means, Emergency tax codes, If you have a K in your tax code. Checked 25 September 2026. Not every possible code is published by GOV.UK; this tool says so rather than guessing.
Want to see what your code means for your pay? Try the UK Take-Home Pay Calculator.