UK Employer National Insurance Calculator
Estimate your employer National Insurance contribution (Class 1 secondary NICs) from gross pay. This calculator is designed for standard Category A style calculations and supports multiple tax years.
This is an estimate tool, not tax advice. Always confirm payroll values against current HMRC guidance and your payroll software.
What is employer NI?
Employer NI (National Insurance) usually refers to Class 1 secondary contributions paid by employers on employee earnings above the secondary threshold. It is separate from the employee’s own NI deductions and is an additional payroll cost borne by the business.
If you hire staff in the UK, understanding this cost is essential for:
- setting realistic salary budgets,
- forecasting monthly payroll cash flow,
- pricing projects and services accurately, and
- planning growth and recruitment.
How this calculator works
At a high level, the estimate uses this standard formula:
Employer NI = max(0, Annual Gross Pay − Secondary Threshold) × Employer NI Rate
If you enable Employment Allowance, the calculator then reduces the total employer NI by your available allowance amount (up to the amount of NI due).
Inputs included
- Gross pay per employee (annual, monthly, or weekly),
- number of employees (for total business estimate),
- tax year preset for NI rate and threshold,
- optional Employment Allowance deduction.
Tax year presets used
The calculator includes practical presets to speed up planning. Values can change over time, so always verify before payroll submission:
- 2024/25: 13.8% rate, £9,100 annual secondary threshold, typical Employment Allowance up to £5,000.
- 2025/26: 15.0% rate, £5,000 annual secondary threshold, typical Employment Allowance up to £10,500.
These presets are for quick estimation and may not reflect every relief, category, or legislative update that applies to your specific payroll.
Worked example
Imagine one employee on £30,000 annual pay in the 2025/26 preset:
- Taxable earnings for employer NI: £30,000 − £5,000 = £25,000
- Employer NI before allowance: £25,000 × 15% = £3,750
- If no allowance is applied: annual employer NI is £3,750
With multiple employees, the same per-employee logic is multiplied by headcount, then any Employment Allowance is deducted from the total.
When this estimate may differ from real payroll results
Real payroll can be more complex than a single formula. Differences can occur because of:
- director NI methods and period handling,
- special NI categories (e.g., reliefs for eligible employees),
- irregular payments, bonuses, statutory payments, or benefits,
- apprenticeship levy interactions for larger employers,
- payroll software rounding and period-specific calculations.
Employer NI planning tips
1) Model before hiring
Don’t budget only for gross salary. Add employer NI and pension contributions to see the true cost of employment.
2) Track allowance usage monthly
If you qualify for Employment Allowance, monitor how quickly it is consumed during the year so there are no cash flow surprises later.
3) Re-check after tax year changes
Rates and thresholds can move at the start of a tax year. Refresh assumptions in April and update internal forecasts.
Frequently asked questions
Is this an official HMRC calculator?
No. It is an independent estimator to help with planning. Use payroll software and HMRC guidance for official reporting.
Does this include employee NI?
No. This page calculates employer NI only. Employee NI is separate and deducted from employee pay based on different bands and rules.
Can I use this for sole traders with no employees?
If there are no employees on payroll, employer Class 1 secondary NI will generally not apply in the same way. This tool is aimed at employers running PAYE payroll.
Final note
Use this UK employer NI calculator as a fast planning tool for payroll budgeting, hiring scenarios, and annual forecasting. For filing and compliance, always validate results against up-to-date HMRC publications and your accountant or payroll provider.