Pick any two UK PAYE tax codes and we will line up the allowance, emergency status, region and approximate annual tax on a £30,000 salary so you can see exactly how they differ.
Last updated 2026-04-12
| Attribute | K100 | K300 |
|---|---|---|
| Category | KCode | KCode |
| Region | rUK | rUK |
| Allowance | £-1,000 | £-3,000 |
| Emergency / non-cumulative | No | No |
| Approx. annual tax on £30k | £6,200 | £6,600 |
| In one sentence | Adds £1,000 to your taxable pay because untaxed income exceeds your allowance. | Adds £3,000 to your taxable pay because untaxed income exceeds your allowance. |
Bottom line on £30k
On a £30,000 salary, K100 deducts roughly £6,200 in income tax per year vs £6,600 for K300. That is a difference of £400 per year - K100 is less expensive.
Hand-picked side-by-sides that answer the most-searched UK tax-code questions.
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