Tax Code Guide

K100

Tax Code K100 Explained

What does this code mean?

K100 means £1,000 is added to your taxable income rather than receiving a personal allowance deduction. Your benefits or deductions slightly exceed your personal allowance. For example, if your allowance is £12,570 but your benefits total £13,570, the excess £1,000 is added to your pay for tax purposes.

Who gets this code?

Employees whose company benefits marginally exceed their personal allowance, or those with modest underpayment adjustments.

Is it correct?

Check your latest P45 or Payslip to see if this matches your current situation.

Think you overpaid on K100?

If your tax code was wrong for even a few months, HMRC might owe you money. Upload your P60 or Payslip to check instantly.

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