P11D

A P11D is the end-of-year form an employer uses to tell HMRC about taxable benefits and expenses it gave an employee, such as a company car, private medical insurance or a cheap loan, when these were not taxed through payroll. The employer also files a P11D(b) to report the Class 1A National Insurance it owes.

The rules on GOV.UK, checked 27 September 2026:

• the P11D, the copy for the employee and the P11D(b) are due by 6 July after the tax year; Class 1A must be paid by 22 July (19 July by cheque);
• the Class 1A rate for 2026 to 2027 is 15%, paid by the employer, not you;
• a late P11D(b) costs £100 per 50 employees for each month or part month;
• payrolling becomes compulsory for company cars, car fuel, vans, van fuel and medical benefits from 6 April 2027 and for most other benefits from 6 April 2028. Loans and accommodation stay voluntary.

Example: your P11D shows a £1,000 private medical insurance benefit. As a basic rate taxpayer you pay £200 tax on it, usually collected through a lower tax code, and your employer pays £150 Class 1A.

Check that the benefit has been taken off your allowance correctly with the tax code checker, or cost a company car with the company car tax calculator.