Tax Code · 2026/27

D0 Tax Code — Higher-Rate (40%) on Every Pound UK 2026/27

D0 applies a flat 40% higher-rate to all pay from this source. HMRC uses it when they believe your total income already sits above the basic-rate band.

What the D0 tax code means

The D0 tax code taxes 100% of pay from this source at the higher rate — currently 40% in England, Wales and Northern Ireland. No Personal Allowance is given because HMRC assumes it's used on your primary income.

It's the next step up from BR: HMRC applies D0 when your primary job has already filled the basic-rate band (income over £50,270 in 2026/27) and this additional source pushes you into higher-rate territory.

D0 avoids an under-payment scenario where a second job taxed at BR (20%) would leave you owing the extra 20% at year-end. By collecting 40% at source, HMRC keeps PAYE accurate across both employments.

When you'll see D0

What to do if you have a D0 code

Worked example

£15,000 second-job income on D0 while your main job pays £60,000 (already in higher-rate territory). Income Tax on the second job is 40% × £15,000 = £6,000. Without D0 (e.g. on BR at 20%), you'd pay only £3,000 here and owe £3,000 at year-end through self-assessment.

Want to see the numbers for your own salary? Use the salary calculator and pick 2026/27 to see how D0 interacts with your full take-home.

Frequently asked questions about D0

How is D0 different from BR?
BR applies 20% to all pay; D0 applies 40%. HMRC moves you from BR to D0 when they see your total income is already in higher-rate territory — it's a more accurate collection at source.
I'm only on D0 — does that mean I'm taxed 40% on everything?
D0 applies only to pay from that source (usually a second job or pension). Your primary source keeps its own tax code, typically 1257L with the usual basic-rate band below higher rate.
Can D0 change back to BR or 1257L?
Yes. If your main income drops below the higher-rate threshold, HMRC normally downgrades additional-source codes to BR. Contact HMRC if the code doesn't update automatically after a circumstance change.

All UK tax codes →

Sources & further reading

All figures and definitions on this page reflect the 2026/27 UK tax year and are cross-checked against HMRC guidance.