Tax code · 2026/27

1131N means you can earn £11,310 a year before paying income tax

Tax code 1131N gives you a tax-free personal allowance of £11,310 for the 2026/27 tax year, which is £943 a month or £218 a week. Anything you earn above that is taxed at the England and Northern Ireland rates, starting at 20%. The number is simply your allowance with the last digit removed.

What does each part of 1131N mean?

The number 1131 is your allowance divided by 10: 1131 × 10 = £11,310. HMRC actually lets you earn up to £11,319 before tax because the last digit is dropped.
This allowance is £1,260 lower than the standard £12,570. Common reasons are taxable benefits such as a company car or medical insurance, untaxed income like interest or rent, underpaid tax from an earlier year being collected, or the allowance being tapered because your income is above £100,000.
The N suffix means you have transferred £1,260 of your personal allowance to your spouse or civil partner under Marriage Allowance, so your own allowance is lower.
There is no S or C prefix, so HMRC treats you as living in England or Northern Ireland.

How much tax do you pay with code 1131N?

The table shows income tax and take-home pay in 2026/27 for four salaries with code 1131N, compared with the standard code 1257L. National Insurance is not affected by your tax code.

Salary	Tax with 1131N	Tax on standard code	Take-home with 1131N	Per month
£25,000	£2,738	£2,486	£21,268	£1,772
£35,000	£4,738	£4,486	£28,468	£2,372
£50,000	£7,936	£7,486	£39,070	£3,256
£75,000	£17,936	£17,432	£53,553	£4,463

On £35,000 the effective rate with 1131N is 18.7%, against 17.9% on the standard code, a difference of £252 a year. Use the take-home pay calculator with your own salary, pension and student loan.

Frequently asked questions

Is tax code 1131N correct for me?

Compare 1131N with the standard code 1257L. The difference should match an adjustment you recognise, such as a company benefit, job expenses, Marriage Allowance or an underpayment from an earlier year. If it does not, ask HMRC to review it.

How much tax do I pay on £35,000 with tax code 1131N?

On £35,000 with code 1131N income tax is £4,738 a year in 2026/27, leaving take-home pay of £28,468 (£2,372 a month) after National Insurance of £1,794. On the standard code it would be £4,486.

How do I change tax code 1131N?

You cannot change it yourself; only HMRC can issue a new code. Update your details in your HMRC Personal Tax Account or call 0300 200 3300 with your National Insurance number and details of your income and benefits. HMRC sends the new code to your employer and any tax overpaid in the year is refunded through your pay.

What does the lack of a prefix mean?

No prefix means HMRC treats you as living in England or Northern Ireland. If you actually live in Scotland or Wales, tell HMRC so the correct regional code can be issued.