— free tool · 2025/26 tax year
What's employer NI
really costing you?
Since April 2025, employers pay 15% National Insurance on everything above just £5,000 per employee — and the Employment Allowance that offsets it rose to £10,500 a year. Two minutes here shows you your estimated bill, and what you may be missing.
How employer NI works in 2025/26
Employers pay secondary Class 1 National Insurance at 15% on each employee's earnings above the £5,000 Secondary Threshold. The rate went up (from 13.8%) and the threshold came down (from £9,100) in April 2025 — which is why many businesses' payroll bills jumped this year.
What is the Employment Allowance?
A government allowance that lets eligible employers knock up to £10,500 a year off their employer NI bill. Plenty of businesses never claim it — and claims can be backdated up to 4 tax years. Director-only and connected companies have special rules, which is what our review confirms.
What this calculator doesn't check
Employee NI category letters (the most common leak), RTI submission errors, and salary-sacrifice pension structuring — all legitimate savings this quick estimate can't see. The free payroll review checks the lot and gives you an exact number.