Employer NI Calculator (UK)
Estimate Class 1 secondary (employer) National Insurance for a single employee using common Category A settings.
Important: This is an estimate for planning payroll costs. It does not include every category letter, relief, director method, or irregular pay rule.
What is employer NI in the UK?
Employer NI (National Insurance) usually means Class 1 secondary contributions paid by employers on employee earnings above the secondary threshold. In practice, this is one of the biggest payroll costs on top of gross wages and pension contributions.
If you run payroll, understanding this figure helps with:
- Staff budgeting and recruitment planning
- Cash-flow forecasting for monthly PAYE payments
- Comparing full employment cost vs gross salary offers
- Avoiding surprises at year-end
How this employer NI calculator works
This tool uses a simple formula for standard Category A style calculations:
Employer NI = (Qualifying earnings above secondary threshold) × employer NI rate
You choose your pay period (weekly, monthly, annual), enter gross pay, and select the tax year. The calculator then estimates:
- Employer NI for that pay period
- Annualised employer NI
- Total employer cost (gross pay + employer NI)
- Optional reduction from Employment Allowance
Common Category A reference rates used in this page
| Tax year | Employer NI rate | Secondary Threshold (annual) | Secondary Threshold (monthly) | Secondary Threshold (weekly) | Employment Allowance in calculator |
|---|---|---|---|---|---|
| 2024/25 | 13.8% | £9,100 | £758 | £175 | £5,000 |
| 2025/26 | 15% | £5,000 | £417 | £96 | £10,500 |
Threshold and allowance values can change with legislation. Always check HMRC guidance for live payroll processing.
Quick example
Suppose you pay an employee £3,000 monthly in 2025/26:
- Monthly threshold = £417
- NI-able pay = £3,000 - £417 = £2,583
- Employer NI = £2,583 × 15% = £387.45 per month
That means your monthly employer cost for this employee is roughly £3,387.45, before pensions, apprenticeship levy (if applicable), bonuses, and benefits.
When to use an employer national insurance calculator
1) Hiring and offer planning
A salary offer of £35,000 is not a £35,000 cost. The actual cost is salary plus employer NI and any other employment costs.
2) Department budget models
Finance teams can model scenarios quickly by changing salary and pay period assumptions to see annual payroll impact.
3) Contractor vs employee comparisons
If you are comparing different ways of engaging talent, employer NI is a key variable in total cost of employment.
What this calculator does not include
- Different NI category letters beyond a simplified standard approach
- Age-specific rules and specialist reliefs
- Director annual earnings method complexities
- Apprenticeship Levy calculations
- Pension auto-enrolment contributions
- Benefits-in-kind/Class 1A treatment
If your payroll includes any of these, treat this as an initial estimate and confirm via payroll software or accountant review.
FAQ: employer NI calculator UK
Is this the same as employee NI?
No. Employee NI is deducted from employee pay. Employer NI is paid by the employer as an additional business cost.
Does Employment Allowance remove all employer NI?
Not always. It can reduce your total annual employer NI bill up to the available allowance, but not below zero.
Can I use this for weekly payroll?
Yes. Switch pay period to weekly and enter gross weekly pay.
Is this suitable for real-time filing submissions?
No. Use RTI-compliant payroll software for live submissions. This page is for planning and estimation.
Final thoughts
If you are searching for an employer NI calculator UK, the most useful tool is one that turns salary figures into true employment cost quickly. Use this page to model scenarios, then validate with up-to-date HMRC rules before final payroll decisions.
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