Why am I on emergency tax?

Emergency tax usually applies when HMRC doesn't yet have full details of your income — typically after starting a new job without a P45, starting your first job, going from self-employed to employed, or receiving company benefits. It's a temporary code until HMRC issues the correct one.

How do I get my emergency tax back?

Once HMRC issues your correct tax code to your employer, any overpaid tax in the same tax year is usually refunded automatically through your next payslip. If the year has ended, HMRC reconciles it and sends a refund, or you can claim via your Personal Tax Account.

Emergency Tax Codes Explained

Just started a new job and your first payslip looks brutal? You're probably on an emergency tax code. Here's what the codes mean, why it happened, how much extra you're paying — and how to get it back.

By Mike Turzynski · 5 min read · Tax year 2026/27 · Updated June 2026

What an emergency tax code looks like

Check your payslip for the tax code. An emergency code is usually the standard 1257L followed by W1, M1 or X — or one of the no-allowance codes:

Code	What it means
`1257L W1`	Week 1 basis — tax calculated on this week's pay alone, ignoring what you've earned earlier in the year.
`1257L M1`	Month 1 basis — same idea, for monthly-paid workers.
`1257L X`	Generic non-cumulative ("emergency") basis used by some payroll systems.
`0T`	No Personal Allowance at all — you're taxed from the very first pound. Often applied when you start a job with no P45 and don't complete a starter checklist.
`BR`	All income taxed at the basic rate (20%) with no allowance — common on a second job, but sometimes applied in error.

The key difference: codes ending W1/M1/X still give you the £12,570 allowance, but only a slice of it each period and without "catching up" on earlier months. Codes like 0T and BR give you no allowance at all — those hit hardest.

Why you've been put on emergency tax

Emergency tax happens when HMRC or your employer doesn't have a complete picture of your income yet. The usual triggers:

You started a new job without a P45 from your previous employer.
It's your first ever job, or your first after a long break.
You moved from self-employment to employment.
You started receiving company benefits (car, private medical) or the State Pension.
You have more than one job and HMRC is still allocating your allowance.

How much extra are you paying?

It depends on the code. On a W1/M1 code you might pay roughly the right amount or slightly too much. On 0T or BR you lose the £12,570 tax-free allowance — costing up to £2,514 extra tax over a year (20% of £12,570) while it's in place, and more if it pushes income into higher-rate territory.

The good news: emergency tax is almost always temporary, and you don't lose the money. UK Income Tax is cumulative, so once your correct code is applied, the system recalculates from the start of the tax year and refunds any overpayment automatically.

How to fix it and get your refund

Give your employer your P45 from your last job if you have one — this is the fastest fix.
No P45? Complete the HMRC starter checklist (your employer provides it). This tells HMRC your situation so they can issue the right code.
Check your Personal Tax Account at gov.uk to see what code HMRC holds and update any wrong details (for example, telling them which job is your main one).
Wait one or two pay runs. Once HMRC sends the corrected code to your employer, your next payslip usually includes the refund of any overpaid tax for the year.
If the tax year has ended while you were overtaxed, HMRC reconciles it automatically and sends a P800 with a refund — or you can claim through your Personal Tax Account.

How to check you're now on the right code

The standard code for someone with one job and the full Personal Allowance is 1257L with no W1/M1/X suffix. If you see that on your payslip and your take-home looks right, you're sorted. To confirm what your take-home should be, run your salary through the calculator — if your payslip is lower, you may still be on an emergency code.

Check what your take-home should be ›

General information for the 2026/27 tax year, not financial advice. If your code still looks wrong after two pay periods, contact HMRC on 0300 200 3300 or via your Personal Tax Account. See our tax code guides for what each code means.

Written and reviewed by Mike Turzynski, founder of Paycheckly. Last updated June 2026. Questions or corrections? Email us.