P11D(b)
UK tax glossary · Last reviewed: April 2026
Employers who provide taxable benefits must submit both individual P11D forms (one per employee) and a P11D(b) summary by 6 July after the tax year. The P11D(b) calculates Class 1A NI at 13.8% (rising to 15% from April 2025 on new benefit packages) on the total value of benefits.
Class 1A NI is an employer-only charge — employees do not pay it. However, employees do pay Income Tax on the benefit value through their adjusted tax code or Self Assessment.
Late P11D(b) submissions attract a £100 per month penalty per 50 employees. HMRC may also charge interest on late Class 1A NI payments, which are due by 19 July (or 22 July for electronic payments).
Common questions
Does every employer have to submit a P11D(b)?
Only employers who have provided taxable benefits or expenses that are not covered by a PAYE Settlement Agreement. If no P11Ds are filed for the year, a nil P11D(b) may still be required to confirm this.
How is Class 1A NI calculated?
It is 15% (from April 2025) of the total cash equivalent of all benefits reported on P11D forms for the year. The P11D(b) aggregates all individual P11Ds and computes the total Class 1A charge.
Related resources
TaxHelper provides general information based on published HMRC rates and guidance. It is not regulated financial or tax advice. For decisions involving significant sums, complex circumstances, or if you are unsure, speak to a qualified accountant or HMRC directly.