UK tax codes · 2026/27 tax year

1257M and 1383M tax codes: Marriage Allowance received

The letter M in a tax code means you have received Marriage Allowance: your husband, wife or civil partner has transferred 10% of their Personal Allowance, £1,260, to you. Added to your own £12,570 that gives you £13,830 tax-free, so the code usually reads 1383M rather than 1257M. It cuts your Income Tax by up to £252 a year: on £25,000 you pay £2,234 instead of £2,486.

Tax code rules checked against GOV.UK and HMRC's PAYE Manual on 25 September 2026.

Transferred to you

£1,260

10% of partner's allowance

Your tax-free pay

£13,830

code 1383M

Tax saved

£252

a year, basic rate

Tax on £25,000

£2,234

vs £2,486 on 1257L

1383M compared with 1257L in 2026/27

Income Tax a year for the partner receiving Marriage Allowance, England, Wales and Northern Ireland rates. The £60,000 case is left out because a higher-rate payer cannot receive the allowance.

Salary	Tax on 1383M	Tax on 1257L	Saved
£20,000	£1,234	£1,486	£252
£25,000	£2,234	£2,486	£252
£40,000	£5,234	£5,486	£252

Who can receive it

You must be married or in a civil partnership, your partner must earn less than their Personal Allowance (usually £12,570), and you must pay tax at the basic rate, which usually means income between £12,571 and £50,270. In Scotland you must pay the starter, basic or intermediate rate, usually £12,571 to £43,662. Couples who only live together cannot claim.

Why 1383M and not 1257M

The number is your tax-free amount with the last digit dropped. £12,570 plus £1,260 is £13,830, so HMRC's code is normally 1383M. If your code shows 1257M, the M still means you receive the allowance, but the number shows HMRC has taken something else off; check the breakdown in your HMRC account.

How the code changes

GOV.UK says HMRC gives your partner's allowance to you by changing your tax code, which can take up to 2 months, or through your Self Assessment return. Successful claims are backdated to 6 April, and claims can go back to the 2022 to 2023 tax year.

The £60,000 case

At £60,000 you pay 40% tax on part of your pay, so you cannot receive Marriage Allowance. If an M code stays on your pay after you move into the higher band, HMRC will collect the difference. Ask your partner to cancel the claim, which runs to the end of the tax year.

If you think this code is wrong

If you have an M code but your partner has not claimed Marriage Allowance, or your circumstances have changed, check your details. Sign in to HMRC's Check your Income Tax service (gov.uk/check-income-tax-current-year) and check your jobs, pensions, benefits and expenses. HMRC then tells you and your employer any new code within 15 working days; it should show on your next or following payslip if you are paid monthly, or your third if weekly. If you cannot go online, call the Income Tax helpline on 0300 200 3300 (Monday to Friday, 8am to 6pm). After starting a new job, wait 35 days before calling.

Guides and definitions

High Income Child Benefit Charge: how it is worked out and cut (Guide)
How to read your payslip: every line explained, with an example (Guide)
Emergency tax: how it works and how to get your money back (Guide)
Emergency tax code (An emergency tax code, marked W1, M1 or X, taxes each payday on its own, as if you were paid that amount every period of the year.)
P11D (A P11D is the form UK employers send HMRC by 6 July to report each employee's taxable benefits and expenses that were not taxed through payroll.)
P60 (A P60 is the yearly summary of your pay and tax from one employer, due by 31 May if you work there on 5 April.)
Personal Allowance (The Personal Allowance is the income you can earn each UK tax year before Income Tax starts: £12,570 for 2026/27.)
Tax code (A UK tax code tells your employer or pension provider how much tax-free pay to give you; 1257L, meaning £12,570, is the most common.)

Check your own tax code and pay

Other tax codes explained

1257L tax code (Standard tax-free allowance of £12,570 on one job or pension)
Emergency codes (W1, M1, X) tax code (Emergency basis: each payment taxed on its own)
S1257L tax code (Standard allowance, taxed at Scottish rates)
C1257L tax code (Standard allowance, taxed at Welsh rates)
1257N / 1131N tax code (You transfer £1,260 of Marriage Allowance to your partner)
BR tax code (All pay taxed at the 20% basic rate, no allowance)
0T tax code (No tax-free pay; all pay taxed through the bands)
D0 tax code (All pay taxed at the 40% higher rate)
D1 tax code (All pay taxed at the 45% additional rate)
SD0, SD1, SD2, SD3 tax code (Scottish flat-rate codes at 21%, 42%, 45% or 48%)
K codes tax code (Untaxed income or deductions bigger than your allowance)
NT tax code (No tax taken from this job or pension)

Every UK tax code in one table · Salary after tax calculator · Check your own tax code and pay

Common questions

What does M mean in my tax code?

GOV.UK says M means Marriage Allowance: you have received a transfer of 10% of your partner's Personal Allowance. For 2026/27 that is £1,260, which reduces your tax by up to £252.

Why is my tax code 1383M?

Because your tax-free amount is £13,830: the standard £12,570 plus £1,260 transferred from your partner. HMRC drops the last digit and adds M, the letter for someone receiving Marriage Allowance.

How much does Marriage Allowance save?

Up to £252 a year for the person receiving it. On £25,000 you pay £2,234 on 1383M instead of £2,486 on 1257L. The saving is smaller if your pay is only just over £12,570.

Does the M tax code carry on every year?

Yes. The allowance transfers automatically every year until your partner cancels it, for example because their income rises or your relationship ends. If it is cancelled because income changed, it runs until the end of that tax year.

Who should claim Marriage Allowance?

If neither of you has income other than wages, GOV.UK says the lower earner makes the claim. They then get an N code and you get the M code. It can be done online, or through Self Assessment if they file a return.

Sources and assumptions

Income Tax for the 2026/27 tax year (6 April 2026 to 5 April 2027), with the same pay every payday for the whole year.
The code number is read as GOV.UK describes it: the tax-free amount with the last digit dropped (1257 = £12,570). Payroll tables can differ by a few pounds.
National Insurance, pension contributions and student loans are not included unless a table says so.
Marriage Allowance is shown as HMRC codes it: £13,830 of tax-free pay on 1383M.

These are estimates to help you read your tax code, not tax advice. HMRC and your employer's payroll decide the tax you actually pay.