A benefit in kind is usually a non-cash benefit you get from your employer outside your normal salary, and some of these benefits are taxable. If a benefit is taxable, HMRC will often collect the tax by changing your tax code, so you pay a bit more tax each pay period rather than getting a separate bill.
What counts as a benefit in kind?
A benefit in kind, often shortened to BIK, is something your employer provides that has value but is not paid to you as wages. Some benefits are taxable and some are exempt. The key point is that a taxable benefit can increase the amount of tax you owe even if your cash salary stays the same.
Common examples include a company car, private medical insurance, cheap or interest-free loans, and accommodation provided by your employer.
Benefits can also include assets made available for personal use, or services your employer pays for on your behalf.
Not every workplace perk is taxed in the same way. Some are fully taxable, some have special rules, and some are exempt.
How does a benefit in kind affect my tax code?
A taxable benefit in kind usually reduces the tax-free allowance shown in your tax code. That means more of your pay is taxed through PAYE. You do not normally pay tax on the benefit as a separate line item each month. Instead, HMRC adjusts your code so the tax is collected from your salary over the tax year.
For example, if you normally have the standard Personal Allowance of £12,570, your code may reflect that. If HMRC then includes a taxable benefit, it can reduce the allowance built into your code. A lower allowance means a lower code number, and that usually means less take-home pay.
Higher taxable benefits usually mean a lower tax code.
If your benefit changes during the year, HMRC may issue a new code.
If the code is wrong, you could pay too much or too little tax until it is corrected.
Do I pay tax on benefits in kind through PAYE?
Usually, yes. Many employees pay the tax on benefits in kind through PAYE because HMRC adjusts the tax code. This is often called coding out the benefit. It spreads the tax across the year rather than leaving a lump sum at the end.
In some cases, the benefit may be reported after the tax year and HMRC may then update your tax code for a later year, or send a calculation if tax is still due. The exact timing can depend on how the employer reports the benefit and when HMRC processes it.
Does a benefit in kind reduce my take-home pay?
Yes, if the benefit is taxable, your take-home pay can fall because you pay extra tax through payroll. But the benefit itself is not usually taken out of your salary as cash. What changes is the tax you owe because HMRC treats the perk as taxable value.
This can catch people out. You might keep the same headline salary, gain a new work perk, and then notice your net pay has dropped slightly. That does not always mean payroll made a mistake. It may simply mean the tax code has been updated to reflect the benefit.
Do benefits in kind affect National Insurance?
They can, but not always in the same way they affect Income Tax. For employees, the main visible effect is often on Income Tax through the tax code. National Insurance on benefits does not usually appear in exactly the same way as PAYE tax code adjustments, and the employer may also have separate National Insurance obligations on the benefit.
Your normal salary is still subject to employee National Insurance under 2026/27 rules. For employees, National Insurance starts above £12,570, is charged at 8% up to £50,270, and 2% above that. A benefit in kind does not simply slot into those salary deductions in the same way as ordinary pay, so it is worth checking the payslip notes and the tax code notice rather than assuming the whole effect is NI.
Why has my tax code changed after getting private medical insurance or a company car?
Because these are common taxable benefits. HMRC may estimate the annual taxable value of the benefit and reduce the allowance in your tax code by that amount. The result is that more tax is collected from your pay over the year.
A company car is a common example because it often has a clear taxable value and can be added to your HMRC record. Private medical insurance is another common one. If you start, stop or change either benefit, your code may change again.
How can I check if my benefit in kind is in my tax code?
Check your PAYE tax code notice from HMRC and compare it with your payslip. HMRC usually lists the items included in the calculation, such as your Personal Allowance and any deductions for benefits. If you can see a line for medical insurance, company car or another benefit, that is usually the reason your code changed.
Look for a tax code notice or coding notice from HMRC.
Check whether your allowance has been reduced for specific benefits.
Compare the notice with your actual work benefits and recent payslips.
If something looks old or duplicated, HMRC may be using outdated information.
What happens if the benefit in kind amount in my tax code is wrong?
If the amount is wrong, you may pay the wrong tax through PAYE. That can mean underpaying during the year and facing a later adjustment, or overpaying and then waiting for a refund. The practical fix is to check the benefit listed by HMRC against what your employer actually provides.
This often happens when a benefit has ended, changed value, or only applied for part of the year. A tax code can also still include an old company car or an old insurance policy. If the details do not match your situation, it is worth checking with payroll and HMRC so the record can be updated.
Do I need to do anything if I receive a benefit in kind?
Usually, your employer reports the benefit and HMRC updates your tax code. You may not need to take any action if the figures are correct. The main thing is to notice that a benefit can affect tax even though it is not extra salary.
If you are comparing jobs or looking at the real value of a package, look at the cash salary and the tax effect of any benefits together. A perk can still be valuable, but the tax treatment matters when you are working out take-home pay.
How can I work out the pay impact of a benefit in kind?
Start with your gross salary, then check how a lower tax code would affect your net pay. The exact effect depends on the taxable value of the benefit and your tax band. If your income sits partly in the basic rate band and partly in the higher rate band, the same benefit can have a different tax cost than it would for someone on a lower salary.
For 2026/27, the standard Personal Allowance is £12,570, basic-rate tax applies up to £37,700 above that, higher-rate tax applies above that, and the Personal Allowance starts to taper away from £100,000. That means taxable benefits can be more noticeable for some earners than others, especially if the benefit pushes more income into a higher-tax range or interacts with allowance tapering.
If you want a practical estimate, use a take-home pay calculator and compare your normal salary with a version that reflects the reduced allowance or changed taxable pay. That gives you a clearer view of the monthly effect than looking at the tax code in isolation.