Your jobs and code
Reduce this if benefits, untaxed income or HMRC adjustments have already cut your allowance.
Estimated take-home from the second job
£0
Likely annual under or over-withholding: £0
What this means
A second-job code changes how tax is withheld through the year. If the code is too generous, you can get more take-home now but owe tax later. If it is too harsh, you may get a refund later.
Worked examples — see the maths on real numbers
How HMRC handles tax codes when you have two PAYE jobs running simultaneously.
Rachel — main job £30,000, evening job £8,000
| Main job (Tax code 1257L) | £30,000 |
| Second job (Tax code BR) | £8,000 |
| Combined gross income | £38,000 |
The maths:
- Main job: Personal Allowance applied. Tax: (£30,000 − £12,570) × 20% = £3,486
- Second job: BR (basic-rate) code means 20% on all earnings, no allowance: £8,000 × 20% = £1,600
- Total tax: £5,086
- Check: combined taxable income £38,000 − £12,570 = £25,430 × 20% = £5,086 ✓
Result: Rachel is taxed correctly because BR was applied to the second job. If the second job had also used 1257L, her £8,000 there would have been covered by a second, duplicate allowance, so no tax would have come off it and she would have under-paid by £8,000 × 20% = £1,600. HMRC would then send a tax calculation (P800) after the year end and usually collect it through a later tax code.
David — main job £55,000, second job £15,000
| Main job (Tax code 1257L) | £55,000 |
| Second job (default Tax code BR) | £15,000 |
| Combined gross income | £70,000 |
The maths:
- Main job: £7,540 basic-rate + (£42,430 − £37,700) × 40% = £7,540 + £1,892 = £9,432
- Second job at BR: £15,000 × 20% = £3,000
- Total deducted: £12,432
- Actual tax due (combined): basic-rate £7,540 + higher-rate (£70,000 − £50,270) × 40% = £7,540 + £7,892 = £15,432
- Under-payment: £15,432 − £12,432 = £3,000
Result: David is under-taxed by £3,000. His main job already uses the whole basic-rate band, so the second job needs a D0 code (40% from the first pound). After the year end HMRC will send a P800 tax calculation or, for amounts it cannot collect through a tax code (including debts over £3,000), a Simple Assessment. Better: check both codes in your HMRC online account during the year so they can be corrected before the underpayment builds up.
Figures use 2026/27 UK tax-year rates and thresholds. Always verify against your specific payslip or tax statement before acting.
Sources
- GOV.UK, Income Tax rates and Personal Allowances (checked 3 October 2026).
- GOV.UK, What your tax code means, including BR, D0, D1 and 0T (checked 3 October 2026).
- GOV.UK, Tax overpayments and underpayments (P800 and Simple Assessment; checked 3 October 2026).
- GOV.UK, Repaying your student loan: what you pay, including more than one employer (checked 3 October 2026).
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