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 | C0T M1 | 1257T |
|---|---|---|
| Category | Emergency | Standard |
| Region | Wales | rUK |
| Allowance | £0 | £12,570 |
| Emergency / non-cumulative | Yes | No |
| Approx. annual tax on £30k | £6,000 | £3,486 |
| In one sentence | Welsh taxpayer version of 0T. Currently identical in cash terms to the rUK code. on a non-cumulative (M1) basis. | Standard allowance, but with items HMRC needs to review (T = "to be reviewed"). |
Bottom line on £30k
On a £30,000 salary, C0T M1 deducts roughly £6,000 in income tax per year vs £3,486 for 1257T. That is a difference of £2,514 per year - C0T M1 is more expensive.
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