Updated for 2025/26 tax year
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Tax Code Checker

Understand what your HMRC tax code means and check if it is correct.

Details

Results

Tax-Free Allowance

£12,570

Standard personal allowance

Monthly Free Pay

£1,048

Weekly Free Pay

£242

Suffix

L

Number

1257

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Calculators
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Compensation & Benefits

Understanding Your UK Tax Code

Your tax code is a short sequence of numbers and letters that tells your employer or pension provider how much tax to deduct from your pay. It is essential for ensuring you pay the correct amount of Income Tax. The numbers in the code usually represent your tax-free Personal Allowance, while the letters provide more information about your tax situation.

For example, the standard code 1257L means you have a tax-free allowance of £12,570. The number is multiplied by 10 to get the allowance amount. At  Calculator Site, we designed this tool to help you quickly decipher any UK tax code. For a full picture of your earnings, see our Take-Home Pay Calculator.

Watch out for Emergency Tax Codes

Calculators & Reference Tools

If your tax code has a suffix like W1, M1, or X, you are on an emergency tax code. This usually happens when you start a new job. It means tax is calculated only on what you are paid in the current pay period, not the whole year, which can often lead to overpaying tax. You can correct this by giving your employer your P45 or by contacting HMRC.

Common Tax Code Components

While there are many variations, most people will encounter a few common elements. Understanding these can help you spot potential issues with your pay. You can find more details using our Salary Calculator.

£12,570

Standard Allowance 25/26

L

Most common suffix

K

Deductions exceed allowance

How to use this Calculator Site tool

Simply enter the full tax code from your payslip into the input field at the top of the page. The  calculator will instantly show you your tax-free allowance for the year, along with a breakdown of what the different parts of the code mean. It is the fastest way to check what HMRC is telling your employer about your tax. For official tax code information, visit GOV.UK tax codes guide.

Frequently Asked Questions

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