What does the tax code
1151L mean?
1151L means £1,060 off your allowance. One cause people never anticipate is an interest-free employer loan, where the benefit is the interest you did not have to pay.
Check if 1151L is right for you
Free and instant, no sign-up. HMRC rates for 2026/27, or every year you can still claim.
Add your benefits, pension and Marriage Allowance for a sharper answer.
Get the detailed breakdown + free reclaim guideMost taxable benefits are things you can see: a car on the drive, an insurance certificate, a gym membership. The one that catches people out is a benefit that consists entirely of something that did not happen.
If your employer lends you money interest free or below the going rate, HMRC treats the interest you were spared as a benefit and taxes you on it. Nobody handed you anything. There is no certificate. But there can be a four figure deduction in your code, and 1151L is exactly the sort of code it produces.
- 1151L Tax Code
- An ordinary L-suffix code giving £11,510 of tax-free pay for 2026/27, £1,060 below the standard allowance. The L means normal allowance rules apply. Deductions of this size are employer-provided benefits, and one that is frequently missed is a cheap or interest-free loan, where the taxable benefit is the interest not charged.
How a beneficial loan is taxed
The rule is easier than it sounds. HMRC publishes an official rate of interest. If your employer charges you less than that rate on a loan, the difference between what you would have paid at the official rate and what you actually paid is a taxable benefit.
An interest-free loan is simply the extreme case: you paid nothing, so the whole notional interest is the benefit.
There is an exemption for small loans. Where the total you owe your employer stays below the exempt threshold throughout the tax year, there is no benefit and nothing to report. Cross that threshold and the whole benefit becomes taxable, not just the excess, which is why loans sitting near the limit deserve attention.
The loans people actually have are mundane: season ticket loans for commuting, rental deposit loans, bridging arrangements when relocating for work, hardship or salary advances structured as loans, and professional training or equipment loans.
The season ticket trap
Annual rail season tickets are expensive enough that the loans to buy them can be substantial, and employers offer them precisely because they are helpful. That combination is what makes them the most common surprise on this list.
Someone borrowing a large amount interest free at the start of the year, repaying it monthly, can find a benefit charge arising for a year in which they were, in their own view, simply spreading the cost of getting to work. Nothing improper has happened. The arrangement is entirely ordinary and the tax treatment is entirely ordinary too. It is just invisible until it appears in a code.
Two details soften it. The benefit is calculated on the balance outstanding through the year, not the original amount, so steady repayment reduces it. And if the total stays under the exempt threshold, there is no charge at all.
Worked example: 1151L on a £42,000 salary
- Gross salary: £42,000
- Subtract the 1151L allowance: £42,000 minus £11,510 = £30,490 of taxable income
- All within the basic rate band, which covers the first £37,700 of taxable income, so taxed at 20%
- Income tax for the year: £6,098
- Monthly tax-free pay: £11,510 divided by 12 = £959.17
On the standard 1257L code the same salary produces £29,430 taxable and £5,886 of tax. The deduction costs £212 across the year, or £17.67 a month. For a higher rate taxpayer the same benefit costs £424. Income tax only, National Insurance excluded, and an estimate to confirm with HMRC.
As always, £1,060 is the value of the benefit, not a bill. Nobody is asking for £1,060.
The other things a £1,060 deduction can be
Do not assume a loan without reading the notice. Deductions at this level also arise from:
- Private medical insurance, the most common four figure benefit, covered on our 1152L page
- A small company car benefit, though cars usually produce much larger deductions, as our 757L page shows
- A taxable state benefit, covered on our 1159L page
- Recovery of an underpayment, where £1,060 collects about £212 of debt, explained on our 1160L page
Four quite different mechanisms, one indistinguishable code. Only the description on the notice separates them.
Loans that are written off
There is a second, sharper event to know about, because it is treated quite differently from the interest benefit and catches people at exactly the wrong moment.
If your employer writes off a loan, releasing you from the obligation to repay it, the amount written off is generally treated as taxable income in the year of the write-off. It is not simply the end of a small benefit. It is a one-off charge on the whole outstanding balance.
This tends to arise in circumstances where nobody is thinking about tax. A relocation loan forgiven when someone leaves. A training loan waived. A season ticket balance written off as a goodwill gesture on redundancy. In each case the intention is generous, and the consequence is a taxable amount that can be far larger than any interest benefit ever was.
The practical effect on a tax code can be dramatic. A written-off balance of several thousand pounds produces a deduction of the same size, which can consume your whole Personal Allowance and turn an ordinary L code into a K code.
Two things worth doing if this applies to you. Ask your employer what they will report and when, so the resulting code change is expected rather than alarming. And check whether the amount landed in the right tax year, since a write-off agreed in one year and processed in another can be recorded against either.
A repayment you make yourself is not a write-off and carries no charge. Neither does a loan simply reaching the end of its normal repayment schedule. The charge arises only where the obligation to repay is released.
When it is wrong
The loan is repaid. Once the balance is cleared the benefit ends, but the deduction will carry forward until somebody says so. This is the single most likely error on this page, because loans end on a schedule and codes do not.
The balance has fallen substantially. The benefit depends on the amount outstanding through the year. A loan half repaid should produce a materially smaller benefit than a new one.
You were charged interest. If you paid your employer interest, that reduces the benefit, and it is frequently omitted.
The loan was always within the exempt limit. Then there should be no benefit at all.
You left the employer. A benefit from a job you no longer hold should not be reducing your allowance against a new one.
Getting it corrected
Compare the deduction against your P11D, which is your employer's statement of the benefits it reported. Where the two disagree, the P11D is normally the better evidence. If your employer payrolls benefits instead, the value appears on your payslips and there should be no coding deduction for it at all, so check you are not being taxed through both routes.
Then sign in to your Personal Tax Account at gov.uk/personal-tax-account, open "Check your Income Tax", and report the change. The Income Tax helpline is 0300 200 3300.
A corrected code applies cumulatively, so an overpayment during the current tax year comes back through your next payslip. Earlier years need a separate claim within four years, covered in our guide to reclaiming overpaid tax, and 2022/23 closes on 5 April 2027.
Our free tax code checker will estimate your correct code with and without the benefit. It gives an estimate rather than advice.
People also ask
- 1151L gives £11,510 of tax-free pay, £1,060 below the standard allowance
- A cheap or interest-free employer loan is a taxable benefit, and the benefit is the interest you did not pay
- HMRC publishes an official rate of interest, and the charge is the shortfall against it
- Small loans below the exempt threshold produce no benefit at all
- Season ticket, rental deposit and relocation loans are the ones people least expect to be taxed
- The benefit is based on the balance outstanding through the year, so repayment reduces it
- The deduction will not disappear when the loan is repaid unless you tell HMRC
Related tax codes: 1152L tax code | 1159L tax code | 1160L tax code | 757L tax code | 1257L tax code
Stop calculating manually.
TapTax connects to your bank, categorises expenses automatically, and submits quarterly updates to HMRC. Free plan, no card required.