0T tax code meaning: no allowance and how it differs from BR

0T means the Personal Allowance is zero for that job, so pay is taxed through the bands from the first pound. It appears when a new starter has no P45 and does not complete a starter checklist.

Updated 9 October 2026. Facts checked against GOV.UK and legislation.gov.uk on 9 October 2026.

What 0T means

GOV.UK describes 0T as the code used when your Personal Allowance has been used up, or when you have started a new job and your employer does not have the details they need to give you a tax code. The T means your code includes other calculations to work out your Personal Allowance. In practice, the 0 means the allowance comes out at zero.

Put simply, 0T means no tax-free amount is given on that job. Pay is taxed using the tax bands, starting from the first pound.

0T and BR are not the same

Both codes have no Personal Allowance. The difference is how the rate is applied. BR charges 20% on everything from that job, whatever you earn. 0T uses the tax bands: in England, Wales and Northern Ireland, 20% on the first £37,700 of taxable pay and 40% above that (Scotland has its own bands).

How the bands are applied depends on the 0T. A 0T issued by HMRC works cumulatively, so the band builds up over the year. The 0T given to a new starter with no P45 or checklist is non-cumulative, so each pay period gets only its share of the band, roughly £725 for a week or £3,142 for a month. Pay above that in a single period is taxed at 40%, even if your pay for the whole year would stay under £37,700. That is why 0T can cost more than BR in a busy week or month, not only for higher earners.

The BR tax code: all of a job’s pay taxed at 20%, usually on a second job

When 0T appears

A common cause is a new starter who has no P45 and does not complete the starter checklist. The regulations cover this case. Where a return is sent without the new employee details completed, the employer must deduct tax on a non-cumulative basis using code 0T. Regulation 49A covers new starters who give their employer neither a P45 nor the starter checklist information. It is part of the Income Tax (Pay As You Earn) Regulations 2003.

The other case GOV.UK lists is where your Personal Allowance has already been used up, for example by income from another job or pension that is taxed on your allowance.

What 0T costs you

With no allowance, tax starts from the first pound on that job. At the basic rate, the allowance is worth 20% of £12,570 a year in tax. A 0T code on a job that should carry 1257L takes that tax for as long as the code stays in place.

The regulation says tax is worked out on a non-cumulative basis. That means each pay period stands on its own, so the year-to-date position does not correct an earlier period. The guide on W1 and M1 codes explains what that means in practice.

W1 and M1 emergency tax codes: why each pay day is taxed on its own, and how the code ends

How 0T is corrected

Once a new code arrives after an overpayment, the correction comes through your pay. The emergency tax refund guide explains how and when this happens, and what happens when an overpayment only comes to light after the tax year ends.

Emergency tax refunds: how overpaid tax comes back through your pay or a P800

How to get off an emergency code

A 0T code given because your employer did not have your details when you started is usually temporary. Giving your employer your P45, or a completed starter checklist, normally ends it once HMRC sends a new code, and the W1 and M1 guide sets out the steps.

W1 and M1 emergency tax codes: why each pay day is taxed on its own, and how the code ends

What to check on your payslip

Start with the code. A 0T code on a job where you have no P45 and no checklist is the case to check first.

Whether you gave your employer a P45, or a completed starter checklist, and which statement you chose.
Whether 35 days have passed since you started. If they have and the code is still 0T, contact HMRC.
Whether you have another job or pension. If you do, a BR code may be the right one for this job, not 0T.

Why 0T can last longer than it should

A 0T code can stay in place for a while, because HMRC usually needs details from both your new and previous employers before it issues a new code. Keep a note of your start date, and of the date you gave your employer your P45 or checklist.

If the code has not changed after 35 days, that note helps when you contact HMRC.

Related guides

Sources

This is an estimate, not financial or tax advice. Your payslip is the final figure.