What tax code D1 actually means
Additional Rate on everything: a flat 45% for second incomes of the highest earners.
D1 taxes all income from this source at the 45% additional rate — no allowance, no lower bands. It's issued when your main income already exceeds £125,140, the point where the additional rate begins (and where the personal allowance has fully tapered away). Every pound of a second income is then additional-rate money: £13,500.00 of tax on a £30,000 second income in 2025/26.
- Personal allowance
- £0 against this income
- Applies in
- England, NI & Wales (Scotland uses SD1 at 45% / SD2 at 48%)
- Calculation
- Usually cumulative
See this salary on a different tax code → (opens the main calculator pre-filled with D1)
What does D1 mean?
The additional rate starts once taxable income passes £125,140 — by which point the personal allowance has already tapered to nothing. If your main employment takes you beyond that line, any second PAYE income can only ever be additional-rate income, so HMRC issues D1 and collects 45% at source.
In Scotland the ladder is taller: SD1 corresponds to a 45% deduction and SD2 exists for the 48% Top rate. If HMRC's estimate of your main income is out of date — a bonus that didn't happen, a role change — a D1 code can over-collect substantially, so it's worth keeping your income estimates current in your personal tax account.
When you’ll see D1
- A second job or directorship while your main income exceeds £125,140.
- A large pension drawn alongside a very high salary.
- Multiple PAYE sources where earlier ones exhaust every band below the additional rate.
D1 vs other common codes
| Code | Personal allowance | How income is taxed |
|---|---|---|
| 1257L | £12,570 | Standard bands after the allowance |
| BR | £0 | Flat 20% on everything |
| 0T | £0 | Normal bands from the first pound |
| D0 | £0 | Flat 40% on everything |
D1 questions, answered
Related tax codes
1257L
The standard code for 2025/26 — a £12,570 tax-free personal allowance, applied evenly across the year.
Decode itEmergency tax (W1/M1/X)
Usually a 1257L code with a W1, M1 or X suffix — each payday taxed in isolation until HMRC confirms your details.
Decode itBR
Basic Rate on everything: 20% from the first pound, no personal allowance — normal for second jobs and pensions.
Decode it0T
Zero allowance, but normal bands: 20%, then 40%, then 45% — from the very first pound you earn.
Decode itScottish tax codes (S)
An S at the front of your code means Scottish rates: six bands from 19% to 48% in 2025/26.
Decode itK codes
The code that works in reverse: instead of tax-free pay, a K code adds to your taxable income.
Decode itNot sure this is the right code for you?
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Sources: tax codes — gov.uk · income tax rates · Scottish income tax