NHS Tax Code Explained: 1257L, BR, Emergency Tax and Two Jobs

Last updated: 28 September 2026 · Figures verified against the NHS Employers 2026/27 pay circular.

By the NHS Bands Pay editorial team

What a tax code actually is

Your tax code is a short instruction from HMRC to your employer's payroll, and it appears on every payslip, usually near your NI number. It tells payroll two things: how much of your pay is tax-free, and at what rates the rest should be taxed. Payroll cannot change it, argue with it, or override it — only HMRC can issue a new code, and your employer must use whatever HMRC sends.

The standard code for 2026/27 is 1257L. The number is your tax-free personal allowance divided by ten: 1257 × 10 = £12,570, the personal allowance for the year. The letter L means you are entitled to the standard personal allowance. With this code, the first £1,047.50 of each month's taxable pay is tax-free, the next slice up to £4,189.17 a month is taxed at 20%, and anything above that at 40% (then 45% over £10,428.33 a month).

One subtlety that catches NHS staff out: your tax code applies to your taxable pay, not your gross pay. Because NHS pension contributions are deducted before tax through the net pay arrangement, a Band 5 nurse earning £2,672.75 gross with £221.84 pension has taxable pay of £2,450.91 — and the personal allowance is set against that lower figure. Salary-sacrifice schemes work the same way: they reduce the pay your tax code is applied to.

The tax codes NHS staff see most

Codes ending in L, M or N are the common "allowance" codes. If your code has a smaller number than 1257 — say 1100L — your tax-free amount has been reduced, usually because HMRC is collecting tax owed from an earlier year, or accounting for untaxed income such as rental income or certain benefits. The coding notice HMRC sends you (or shows in your Personal Tax Account) explains exactly why.

Scottish taxpayers get an S prefix (S1257L). The S does not change the allowance; it tells payroll to apply Scottish income tax rates and bands instead of the rest-of-UK ones. If you move across the border, HMRC decides your taxpayer status from where your main home is — tell them when you move, because the wrong prefix means the wrong rates.

Emergency tax: new starters and no P45

"Emergency tax" is not a special punishment rate. It is simply what happens when your new trust's payroll does not yet have enough information to give you a proper cumulative code, so it uses 1257L on a week 1/month 1 basis — sometimes 0T instead. Week 1/month 1 (W1/M1) means each pay period is taxed in isolation, without reference to what you earned earlier in the tax year.

This is standard for new starters who do not provide a P45. Instead, you complete a starter checklist (the form that replaced the P46), declaring whether this is your only job (statement A), you have another job (statement B), or you are receiving a pension (statement C). Statement A with no P45 gets you the 1257L W1/M1 emergency code; statement B typically lands you on BR.

Emergency tax often means you overpay in your first month or two, particularly if you were unemployed or a student before starting. The fix is automatic: once HMRC processes your starter information and issues your cumulative 1257L code, PAYE recalculates your tax across the whole year to date and refunds the difference through your pay. You do not need to claim it, and you do not need to phone anyone — though if the correct code has not arrived after six to eight weeks, it is worth checking your Personal Tax Account to see what HMRC holds for you.

The genuine 0T emergency code is harsher: it gives no personal allowance at all, so a full month's pay is taxed from the first pound. If you see 0T on your payslip, prioritise getting your P45 or starter details to payroll and checking with HMRC, because every month on 0T is a month of overpaid tax waiting to be reclaimed.

Two jobs: bank shifts, agency and second posts

NHS staff with more than one income source live in tax-code land permanently. The rule is simple: your personal allowance can only be used once, so HMRC gives the full allowance to your main job and taxes the second income without it. In practice that means:

Main NHS post: 1257L. Your substantive trust applies the full £12,570 allowance.

Bank shifts at the same or another trust: usually BR. Every pound of bank pay is taxed at 20%, with no allowance. This is correct and expected — your allowance is already being used by your main job. Unsocial-hours enhancements on bank shifts are taxed in exactly the same way.

D0 instead of BR. If your combined income takes you into the 40% band (over £50,270 a year), HMRC may put your second job on D0 so the right amount is collected during the year rather than landing as a bill later.

Where people come unstuck is when the split is wrong: both jobs on 1257L (underpaying tax all year, then a P800 bill in summer), or BR on the main job and 1257L on a tiny bank post (overpaying all year). Either way the mechanism to fix it is the same — tell HMRC your estimated total income from each job for the year, and they will reissue the codes. You can do this in your Personal Tax Account or the HMRC app without phoning.

A related trap: if you do bank shifts through an agency rather than the trust's own bank, the agency is a separate employer with its own payroll. The same allowance-splitting logic applies, and agency payrolls are notorious for defaulting new starters to BR or 0T. Check the first agency payslip, not the tenth.

How to check and fix your tax code

Your payslip shows the code your employer is using; HMRC's records show the code it has issued. If they differ, or if the code looks wrong, the source of truth is your Personal Tax Account on GOV.UK (or the HMRC app), which shows your current code, the coding notices behind it, and your estimated income for the year.

To change a code, you deal with HMRC, not your trust's payroll — payroll staff literally cannot alter it. Useful things to update with HMRC include: starting or leaving a second job, a big change in bank-shift income, moving between England and Scotland, company benefits starting or stopping, and untaxed income HMRC does not know about. After you update your details, the new code is sent to your employer electronically and usually appears within one or two pay cycles.

Timing matters at the edges of the tax year. Codes are reviewed each spring, and the 2026/27 codes were issued before 6 April 2026. If your code changes mid-year, the new code can be backdated to 6 April, and the cumulative PAYE calculation will sweep up any under- or overpayment automatically. Only if there is still a discrepancy after the tax year ends does HMRC issue a P800 calculation — the summer letter that says you are owed a refund or owe more tax.

Keep every coding notice HMRC sends. They explain the arithmetic behind your code, and they are the document you will reach for if you ever need to dispute it. Your March payslip's year-to-date tax figure plus your P60 are the other half of the evidence.

How back pay and lump sums interact with your code

Back pay from a late pay award is taxed in the month it is paid, not spread back over the months it relates to. A £265 arrears payment — roughly what three months of the 3.3% 2026/27 award is worth to a Band 5 nurse at the entry step — simply adds £265 to that month's taxable pay. For most staff that stays comfortably inside the 20% band.

It only becomes interesting for higher earners. If a lump sum pushes one month's taxable pay over the monthly higher-rate threshold (about £4,189), that slice is taxed at 40% for that month. Under cumulative PAYE this usually washes out: later months pull the year-to-date average back down and the over-deduction is refunded through pay. But if you are on a non-cumulative W1/M1 code when the lump sum lands, the extra tax is not automatically rebalanced — another reason to get off emergency codes promptly.

Overtime-heavy months behave the same way. None of this changes your annual tax bill in the end; PAYE is designed so that, with the right cumulative code, twelve months of ups and downs produce the correct yearly total. The payslip is just noisier in lump-sum months.

Frequently asked questions

What does the tax code 1257L mean?

It means you get the standard personal allowance of £12,570 for 2026/27 (1257 × 10), and the L confirms it is the standard allowance. The first £1,047.50 of each month's taxable pay is tax-free; earnings above that are taxed at 20% up to the basic-rate limit, then 40%. Most NHS staff in England on their only job should be on 1257L.

Why is my NHS bank job taxed at BR?

BR means 20% tax on every pound with no personal allowance. Your £12,570 allowance can only be used once, so HMRC gives it to your main job and taxes your second income — bank shifts, agency work or another post — without it. This is normal and correct, not an error. If your main job is part-time and your total income is under £12,570, ask HMRC to split the allowance instead.

Am I paying emergency tax and how do I know?

Check your payslip: an emergency code shows as 1257L W1/M1 (or sometimes 0T). It is used for new starters without a P45. The W1/M1 part means each month is taxed in isolation rather than cumulatively, which often means overpaying at first. Once HMRC issues your proper cumulative code — usually within a few weeks of starting — PAYE refunds the difference automatically through your pay.

How do I change my tax code if I have two NHS jobs?

You update HMRC, not your trust's payroll — payroll cannot change codes. In your Personal Tax Account or the HMRC app, check the estimated income HMRC holds for each job and correct it; HMRC will then reissue your codes (typically 1257L on the main job and BR or D0 on the second). The new code reaches your employer electronically and usually applies within one or two pay cycles.

Will I get emergency tax back?

Yes, in almost all cases without doing anything. Once your correct cumulative tax code replaces the emergency W1/M1 code, PAYE recalculates your tax for the whole tax year to date and refunds any overpayment through your wages. If a balance remains after 5 April, HMRC reconciles it with a P800 calculation in the summer. Keep your P45, starter checklist details and payslips until it is resolved.

Does back pay push me into a higher tax band?

It can do for one month, but it rarely changes your annual bill. Back pay is taxed in the month it is paid, so a large arrears lump sum can nudge that month's taxable pay over the 40% threshold. Under a normal cumulative tax code, PAYE rebalances over the remaining months and refunds the extra automatically. Only if you are on a non-cumulative emergency code does the extra tax tend to stick until HMRC reconciles it.

Sources and independence

Source: GOV.UK — Tax codes: overview and what the letters mean.

Source: GOV.UK — Income Tax rates and allowances 2026/27.

Source: GOV.UK — Personal tax account: sign in or set up.

Source: NHS Employers — 2026/27 Agenda for Change pay circular.

This is an independent guide and is not affiliated with the NHS or HMRC. Tax codes, allowances and thresholds are for the 2026/27 tax year and apply UK-wide except where Scottish taxpayer status applies. Only HMRC can issue or change your tax code — your trust's payroll must use the code HMRC sends. If you are unsure about your position, check your Personal Tax Account or speak to HMRC directly.