What is the D0 Tax Code? A UK Guide for Second Incomes and High Earners
If you’ve seen the D0 tax code on your payslip or P45 and wondered what it means you’re not alone. The UK tax system uses various codes to help employers calculate how much tax to deduct from your wages, and D0 is one of the less common but more significant ones.
In this post, we’ll go over;
- What the D0 tax code is
- Who it applies to
- How it affects your income
- What to do if you think it’s wrong
- How to manage tax across multiple jobs
Whether you’re a high earner, have multiple jobs, or are just checking your tax status, understanding the D0 code is crucial for staying compliant and not overpaying.
What Is the D0 Tax Code?
The D0 tax code is used by HMRC to instruct your employer or pension provider to deduct Income Tax at the higher rate of 40% from all earnings under that employment.
This tax code applies when your Personal Allowance (the amount of income you can earn tax-free) is fully used elsewhere usually on your main job or pension.
You might see the D0 code on your payslip if you:
- Have more than one job or receive income from multiple pensions
- Have already used your full Personal Allowance (£12,570 in 2025/26) on another income source
- Earn enough that the second income falls into the higher-rate tax band (£50,271 to £125,140 in England, Wales, and Northern Ireland)
Key point: Unlike standard tax codes such as 1257L, the D0 code doesn’t provide any tax-free portion – 100% of your income from that job is taxed at 40%.
For full guidance, see GOV.UK: Tax codes.
How Does the D0 Tax Code Work?
When you’re assigned the D0 tax code, all income from that job or pension is taxed at the higher rate of 40% with no tax-free allowance applied.
This happens because your Personal Allowance (worth £12,570 in 2025/26) is already being used elsewhere usually by your main employer or pension provider.
Example (2025/26 tax year):
- You have a main job earning £50,000 per year. Your tax code for this job is 1257L, which uses up your Personal Allowance.
- You also have a second job that pays £20,000 per year. Since your tax-free allowance is already accounted for, HMRC assigns the D0 tax code to your second job.
- Your second employer deducts 40% tax from the full £20,000, even though your total income is only just crossing into the higher-rate tax band.
Important note:
This might temporarily result in overpaying tax especially if your total income doesn’t fully fall into the higher-rate band. HMRC will usually balance this through:
- An automatic PAYE adjustment in future months
- A Self-Assessment tax return, if required
The D0 code is designed to prevent underpayment, helping HMRC ensure you’re taxed correctly across all your income sources over the course of the tax year.
For more info on how multiple incomes are taxed, visit GOV.UK: If you have more than one job.
2025/26 Tax Bands (England, Wales, Northern Ireland)
| Band | Income Range (£) | Tax Rate |
| Personal Allowance | 0 – 12,570 | 0% |
| Basic Rate | 12,571 – 50,270 | 20% |
| Higher Rate | 50,271 – 125,140 | 40% |
| Additional Rate | 125,141+ | 45% |
Tip: Scotland has different income tax bands. Check them here.
When Is the D0 Tax Code Used?
HMRC may assign the D0 tax code in situations where your income from a second job or pension should be taxed at the higher rate (40%), and no Personal Allowance is available under that employment.
You might see the D0 code used if:
- Your second job or pension pushes your total income into the higher-rate tax band (above £50,270 for 2025/26).
- HMRC already knows that you’ve used your full Personal Allowance (£12,570) on your main income.
- Your new employer hasn’t received enough information, and a default higher-rate code (like D0) is applied until HMRC reviews your situation.
- You recently started a new job and didn’t provide a P45 or complete a Starter Checklist, leading to emergency tax treatment or conservative coding.
Tip: If you’re on D0 and believe it’s incorrect (for example, if your total income doesn’t exceed the higher-rate threshold), you can ask HMRC to review and issue a corrected tax code.
To check or update your tax code, log in to your HMRC Personal Tax Account.
D0 vs BR vs D1 Tax Codes
It’s easy to confuse D0 with other tax codes, such as BR or D1. Here’s how they differ:
| Code | Tax Rate | Applied To Income | Used When… |
| BR | 20% | All income | No allowance applied; taxed at basic rate |
| D0 | 40% | All income | Higher-rate tax on second job/income |
| D1 | 45% | All income | Additional-rate tax (for £125k+ incomes) |
