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 | SD3 | 1257L-NI |
|---|---|---|
| Category | Scottish | Standard |
| Region | Scotland | NorthernIreland |
| Allowance | £0 | £12,570 |
| Emergency / non-cumulative | No | No |
| Approx. annual tax on £30k | £6,000 | £3,486 |
| In one sentence | Scottish advanced rate (45%) on all income from this source. | Northern Ireland uses the same PAYE codes as England - there is no NI-specific prefix. |
Bottom line on £30k
On a £30,000 salary, SD3 deducts roughly £6,000 in income tax per year vs £3,486 for 1257L-NI. That is a difference of £2,514 per year - SD3 is more expensive.
Hand-picked side-by-sides that answer the most-searched UK tax-code questions.
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