For 2025/26, the employer National Insurance due on a £18,000 salary is £1,950 per year (£162 per month) before any Employment Allowance offset. This is calculated at 15% on earnings above the £5,000 secondary threshold — a change from the 13.8% rate and £9,100 threshold that applied in 2024/25.
£1,950 per year · £162 per month · £38 per week.
NIable earnings: £13,000 (salary minus £5,000 threshold). Rate: 15%.
| Earnings band | Rate | NI due |
|---|---|---|
| Up to £5,000 (secondary threshold) | 0% | £0 |
| £5,001 to £18,000 | 15% | £1,950 |
| Total employer NI | £1,950 |
Both the rate and threshold changed on 6 April 2025, increasing employer NI cost at virtually every salary level.
| Tax year | Rate | Threshold | NI due |
|---|---|---|---|
| 2024/25 | 13.8% | £9,100 | £1,228 |
| 2025/26 | 15% | £5,000 | £1,950 |
| Increase | £722 | ||
Employment Allowance allows eligible employers to reduce their annual employer NI bill by up to £10,500. If fully available, NI due on this salary after the allowance offset is £0.
Eligibility note: sole-director companies may be excluded. Confirm eligibility with HMRC or your accountant. See the Employment Allowance guide for details.
Under-21 employees and apprentices under 25 attract 0% employer NI up to the upper secondary threshold (£50,270), then 15% above that. Use the full calculator to model relief scenarios.
Tax year 2025/26. Employer NI calculated at 15% on earnings above the £5,000 secondary threshold per HMRC guidance. 2024/25 comparison uses 13.8% above £9,100. Employment Allowance eligibility must be confirmed separately. Estimates only — not financial or legal advice.