A P11D is the form your employer uses to report expenses and benefits it has given you that were not put through the payroll and are not covered by an exemption. You should receive a copy by 6 July after the end of the tax year. You do not pay the tax on a P11D directly: HMRC collects it by reducing the number in your tax code, so the cost appears as a larger deduction on every payslip.
What a P11D reports
A benefit in kind is something of value your employer provides instead of cash: a company car, fuel for private use, private medical insurance, an interest-free or low-interest loan, living accommodation, or a gym membership paid on your behalf.
Because it is not cash, it cannot be taxed through the pay line, so it is reported instead. The P11D is the report, and it lists each benefit with the taxable value the rules give it.
Not everything an employer pays for is on it. Expenses that are wholly, exclusively and necessarily incurred in doing your job are exempt and are not reported at all, which is why business travel reimbursed at an approved rate does not appear.
When you should get one
Your employer has to report benefits for a tax year by 6 July following the end of that year, and to give you a copy of the information by the same date.
A separate form, the P11D(b), goes to HMRC at the same time. That one is the employer's declaration of the National Insurance it owes on the benefits, and it is not something you receive or pay.
You will not get a P11D at all if your employer puts your benefits through the payroll instead, which is the other permitted route.
Payrolled benefits: the other route
An employer can register with HMRC to payroll benefits. The taxable value is then added to your pay each period and taxed as it arises, exactly as salary is, and no P11D is needed for those benefits.
On a payslip, that shows up as an addition to taxable pay rather than a deduction. Your gross cash pay is unchanged, your taxable pay is higher, and the tax follows.
Payrolling is the more accurate route, because the tax is collected in the year the benefit is enjoyed rather than a year later through a code. It is also the reason two colleagues with the same car can have very different tax codes.
Payrolling is being made compulsory in stages. HMRC has said that from April 2027 company cars, car fuel, vans, van fuel and employer-provided medical benefits must be payrolled, and that most other benefits follow from April 2028, with loans and living accommodation staying voluntary. None of that changes 2026/27: for this tax year payrolling is a choice your employer registered for in advance, and the P11D is still the route for anything it did not.
How a reported benefit reaches your pay
Where a benefit is reported rather than payrolled, HMRC collects the tax by taking its value out of your tax-free pay for a later year. Your allowance is reduced by the value of the benefit, and the number in your code falls accordingly.
Take a benefit valued at £5,000. Against a Personal Allowance of £12,570, that turns code 1257L into 757L. On a salary of £40,000, income tax for the year rises from £5,486.00 to £6,486.00, a difference of £1,000.00.
If the benefits are worth more than your whole allowance, there is nothing left to reduce and the code becomes a K code instead, which adds to your taxable pay rather than sheltering part of it.
What happens to National Insurance
Most benefits in kind do not attract employee National Insurance. The Class 1 charge is on earnings, and a car or medical cover is not earnings, so your own National Insurance line is usually untouched by a P11D.
Your employer pays Class 1A National Insurance on most of the benefits it reports. That is an employer cost and never a deduction from your pay.
There are exceptions. Some things provided in a form that can readily be converted into cash are treated as earnings and do attract employee National Insurance in the ordinary way, and those go through the payroll rather than a P11D.
What to check on it
Check that every benefit listed is one you actually had, and for the period you had it. A car returned in March that is still reported for the following year is the classic error, and it repeats until someone notices.
Check that nothing is counted twice. A benefit that has been payrolled should not also appear on a P11D or in your tax code, and that double count is the most expensive mistake in this area.
Check the values against what you were told when the benefit was offered. The taxable value of a benefit is set by rules rather than by what it cost you, and it is often not the number anyone quoted.
If something on it is wrong
Go to your employer, because the report is theirs and a correction has to come from the same place. They can submit an amendment to HMRC.
Then check your tax code, because a wrong benefit stays in the code until HMRC is told. Updating your company benefits in the check your Income Tax service is what rebuilds the code.
A benefit removed mid-year does not produce a refund from your employer. It produces a new code, and the overpayment comes back through your pay once that code is applied cumulatively.
Do benefits mean I have to file a tax return?
Not on their own. For most employees, the tax on benefits is collected through the code and nothing else is required.
A return is needed for other reasons: untaxed income, self-employment, or income above the levels at which HMRC asks for one. Where you do file, the P11D figures are what the employment pages of the return are filled in from, alongside your P60.