National Insurance (NI) is a UK tax on earnings that funds state benefits including the State Pension, NHS, and unemployment support. Both employees and employers pay NI contributions. Use this free calculator to see your employee NI, employer NI, student loan repayments, and estimated take-home pay for the 2025/26 tax year.
Your Salary Details
Pre-tax salary sacrifice pension deduction
Annual Breakdown — 2025/26
Monthly & Weekly Breakdown
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Employer Cost
Uses 2025/26 tax year thresholds. This is an estimate — verify with HMRC for official calculations.
How to Use the UK National Insurance Calculator
National Insurance contributions are one of the largest deductions from UK salaries, yet many people are unclear about exactly how much they pay and how the calculations work. This free NI calculator breaks down your employee contributions, employer contributions, student loan repayments, and income tax to show your estimated take-home pay for the 2025/26 tax year. Whether you are evaluating a job offer, negotiating a salary, or simply budgeting, this tool gives you clear numbers in seconds.
Step 1: Enter Your Annual Gross Salary
Enter your total annual salary before any deductions. This is the figure on your employment contract or job offer. If you know your monthly salary, multiply it by 12 to get the annual amount. The calculator uses this figure to determine which NI thresholds and tax bands apply to your earnings.
Step 2: Select Your NI Category
Most employees fall under Category A, the standard rate. Category B applies to married women and widows who hold a valid reduced-rate election certificate (form CF383). Category C is for employees who have reached State Pension age and are therefore exempt from employee NI contributions. Category H is for apprentices under 25, who benefit from a higher upper secondary threshold before NI applies.
Step 3: Choose Your Student Loan Plan
If you have a student loan, select the correct plan type. Plan 1 covers loans taken out before September 2012 in England and Wales, or any time in Scotland and Northern Ireland. Plan 2 covers post-2012 English and Welsh loans. Plan 4 covers Scottish loans from September 2007 onwards. Plan 5 covers post-2023 loans. Each plan has a different repayment threshold, and repayments are calculated at 9% of earnings above that threshold. Postgraduate loans are repaid at 6%.
Step 4: Add Pension Contributions (Optional)
If you contribute to a workplace pension via salary sacrifice, enter the percentage here. Salary sacrifice pension contributions reduce your gross pay before NI and income tax are calculated, giving you tax relief on both. Most auto-enrolment schemes start at around 5% employee contribution. Leave this at 0% if your pension is not through salary sacrifice.
Understanding Your Results
The results show four key figures: your annual employee NI contribution, the employer NI your company pays on top of your salary, any student loan repayment, and your estimated take-home pay after all deductions. The detailed breakdown itemises income tax, NI, and student loan deductions line by line. The monthly and weekly table helps you plan your budget across different time periods. The employer cost section shows the true total cost of employing you, which is useful when negotiating salary or comparing contract vs. permanent roles.
FAQ
Is this National Insurance calculator free?
Yes, this NI calculator is completely free with no signup, no account, and no limits. All calculations run locally in your browser using JavaScript. You can calculate contributions for any salary as many times as you like at no cost.
Is my salary data private?
Absolutely. All calculations happen entirely in your web browser. No salary figures or personal information are ever sent to any server or stored anywhere. You can disconnect from the internet after loading the page and the calculator will still work.
What NI category should I choose?
Most employees should select Category A, which is the standard rate for employees aged 21 and over. Category B applies to married women and widows with a valid election certificate. Category C is for employees over State Pension age. Category H is for apprentices under 25, who benefit from a higher NI-free threshold.
How is National Insurance calculated?
Employee Class 1 NI for 2025/26 is charged at 8% on earnings between the Primary Threshold (£12,570) and the Upper Earnings Limit (£50,270), and 2% on earnings above the UEL. Employer NI is 15% on earnings above the Secondary Threshold (£5,000). The thresholds are applied on an annual basis in this calculator.
Are student loan repayments included?
Yes, you can select your student loan plan (Plan 1, 2, 4, 5, or Postgraduate) and the calculator will show the annual repayment amount. Repayments are 9% of earnings above the plan threshold for Plans 1-5, and 6% for Postgraduate loans. You can also have both an undergraduate and postgraduate loan simultaneously.
What tax year does this calculator use?
This calculator uses 2025/26 tax year thresholds and rates (6 April 2025 to 5 April 2026). NI thresholds and rates can change each tax year, so always verify with HMRC for the most current rates if you are close to a tax year boundary.
Does this calculator include income tax?
Yes, the take-home estimate includes a simplified income tax calculation using 2025/26 rates: 20% basic rate (£12,571 to £50,270), 40% higher rate (£50,271 to £125,140), and 45% additional rate (above £125,140). The personal allowance is £12,570, reduced by £1 for every £2 earned over £100,000.
What is the difference between employee and employer NI?
Employee NI is deducted from your pay and affects your take-home salary. Employer NI is an additional cost paid by your employer on top of your salary — it does not reduce your pay. For 2025/26, the employer rate is 15% on earnings above £5,000, making the total employment cost higher than the gross salary.