What does D0 mean on my tax code?

D0 means every pound of pay is taxed at 40% (UK higher rate), with no Personal Allowance and no basic-rate band applied. The D indicates a flat-rate code; the 0 means higher rate. Usually applied to a second job when the main job has consumed the PA and basic-rate band.

Should I be on D0 if I only have one job?

No. D0 is wrong if you have only one job. Your only job should use 1257L (standard) or another code that applies your Personal Allowance. Phone HMRC on 0300 200 3300 immediately if you see D0 on your single-job payslip — you're being significantly over-taxed.

Will HMRC refund overpaid D0 tax?

Yes, automatically through PAYE once the correct code is applied. The refund appears as a credit on your next 1-2 payslips. No separate claim or form is needed. If you're no longer employed at the company where D0 was applied, HMRC will issue a P800 letter and refund directly.

Why is my tax code D0?

Last reviewed by the UK Tax Drag editorial team · 12 May 2026 · How we review · Next review due 12 May 2027 · See what changed · Report an error

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Tax code D0 means every pound is taxed at 40% higher rate with no Personal Allowance and no basic-rate band applied. D = a flat-rate code; 0 = higher rate. Normally used on a second job when the first job has consumed the £12,570 PA and most of the £37,700 basic-rate band. Wrong D0 codes are uncommon but the over-deduction can be significant.

When D0 is the correct code

D0 is the right code when:

You have two or more employments, and your main job already uses up your full Personal Allowance plus all or most of your basic-rate band.
Your main job pays £50,000+ — so any second-job income would all be taxed at the 40% higher rate anyway.
HMRC has explicitly assigned D0 to the second job to ensure correct overall tax is collected without you needing to file Self Assessment.

Example: you earn £60,000 from your main job (which uses code 1257L) and £5,000 from a part-time second job. HMRC assigns D0 to the second job so all £5,000 is taxed at 40% = £2,000. This correctly captures the higher-rate tax due on that income.

Worked example — main job £60k + second job £5k on D0

Income source	Code	Gross	Tax
Main job	1257L	£60,000	£11,432
Second job	D0	£5,000	£2,000
NI on main	—	—	£3,211
NI on second (Class 1)	—	—	£100
Combined take-home		£65,000	£48,257

D0 ensures you pay the correct 40% on the £5,000 second-job income without needing to file Self Assessment. Without D0, the second job might use a BR code (20%) — leaving you with a £1,000 underpayment to settle at year-end.

When D0 is wrong

D0 is wrong on your only job. Always. If you have just one employer and your payslip shows D0, the code is incorrect and you’re being massively over-taxed.

D0 might also be wrong if:

Your main-job earnings dropped below £50,270 — in which case some of your second-job income should be at 20%, not 40%.
You quit your main job — your second job (now your only job) should switch to 1257L.
HMRC has miscalculated your combined income — happens occasionally with irregular incomes or bonuses.

If D0 is wrongYou’re paying 40% on income that should be taxed at 20% or even 0%. On £5,000 of pay, that’s £1,000-£2,000 of overpaid tax per year. Phone HMRC immediately on 0300 200 3300.

What to do if D0 appears unexpectedly

Action 1: Confirm you actually have a second job in HMRC’s recordsLog into your Personal Tax Account. Under PAYE you’ll see all jobs HMRC has recorded for you. If there’s only one — the D0 is wrong.

Action 2: Check the main-job codeThe main job should be on 1257L (or whatever code uses your PA). If your main job is on BR or D0 instead, your codes are mixed up — both need fixing.

Action 3: Phone HMRC on 0300 200 3300Explain you have only one job (if true) or that your main-job income has changed. HMRC reassigns codes within 1-2 working days. Overpaid tax refunds automatically through PAYE in the next pay period.

Action 4: Consider the second-job tax code calculatorThe second-job tax code calculator shows exactly what code should be assigned to each job given your combined income.

Decode multi-job tax codes

The second-job tax code calculator shows which code each of your jobs should be on given your combined income and tax-band position.

Open the second-job code calculator →

Other UK tax codes explained

Sources and methodology

D0 / D1 code rules from gov.uk/tax-codes. Multiple-jobs PAYE handling from HMRC PAYE Manual gov.uk/hmrc-internal-manuals/paye-manual.

UK Tax Drag is not authorised by the Financial Conduct Authority and does not provide regulated financial advice — see the content disclaimer for the full position. The methodology page documents how every calculator is built and reviewed.

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