Glossary · UK
What is Class 1A National Insurance?
Employer-only NI at 13.8% on benefits in kind such as company cars and private medical insurance, reported on P11D(b) and due by 19 July.
Full Definition
Class 1A National Insurance is a charge payable exclusively by employers (not employees) on the value of benefits in kind provided to directors and employees. Unlike Class 1 NI, which applies to cash earnings and is shared between employer and employee, Class 1A applies only to non-cash benefits and is entirely an employer cost. The rate is 13.8% on the total taxable value of all benefits provided during the tax year. Common benefits subject to Class 1A include: company cars and fuel benefit; private medical or dental insurance; non-business travel and subsistence; living accommodation; low-interest or interest-free loans above GBP 10,000; and gym memberships. Employers report all Class 1A-liable benefits on form P11D(b) (the employer declaration accompanying individual P11D forms) and must submit this to HMRC by 6 July following the end of the tax year. Payment of the Class 1A NI due is required by 19 July (or 22 July for electronic payment). Where an employer has registered to payroll benefits (report them through payroll in real time rather than on P11D), Class 1A is still calculated and paid annually via P11D(b) -- payrolling affects income tax collection but not the Class 1A NI payment process. From April 2026, payrolling most benefits in kind becomes mandatory.