uk-tax-calculator

Complete UK tax calculator for 2025/26. HMRC-accurate Income Tax, National Insurance, Student Loan, Pension, Dividend Tax & Stamp Duty calculations.

Covers England, Scotland, Wales & Northern Ireland.

Try the full interactive calculator at ukcalculator.com

Install

npm install uk-tax-calculator

Quick Start

const { calculateTakeHome } = require('uk-tax-calculator');

const result = calculateTakeHome({
  salary: 50000,
  taxYear: '2025/26',
  region: 'england',
  studentLoan: 'plan2',
  pensionPercent: 5
});

console.log(result);
// {
//   gross: 50000,
//   incomeTax: 7486,
//   nationalInsurance: 2879,
//   studentLoan: 2043,
//   pension: 2500,
//   totalDeductions: 14908,
//   takeHome: 35092,
//   monthlyNet: 2924.33,
//   effectiveTaxRate: 29.82,
//   ...
// }

API

calculateTakeHome(options)

All-in-one take-home pay calculator.

| Option | Type | Default | Description | |--------|------|---------|-------------| | salary | number | required | Annual gross salary in £ | | taxYear | string | '2025/26' | Tax year | | region | string | 'england' | 'england', 'scotland', or 'wales' | | studentLoan | string | 'none' | 'plan1', 'plan2', 'plan4', 'plan5', 'postgraduate' | | pensionPercent | number | 0 | Pension contribution % | | pensionMethod | string | 'salary_sacrifice' | 'salary_sacrifice' or 'relief_at_source' |

calculateIncomeTax(grossSalary, options?)

Income tax with full band breakdown. Supports England and Scottish rates.

const { calculateIncomeTax } = require('uk-tax-calculator');

const tax = calculateIncomeTax(75000, { region: 'scotland' });
console.log(tax.incomeTax);     // Total tax
console.log(tax.breakdown);     // Per-band breakdown

calculateEmployeeNI(grossSalary, options?)

Employee National Insurance contributions.

const { calculateEmployeeNI } = require('uk-tax-calculator');
const ni = calculateEmployeeNI(45000);
console.log(ni.totalNI);  // £2,594.40

calculateEmployerNI(grossSalary, options?)

Employer NI with optional Employment Allowance.

const { calculateEmployerNI } = require('uk-tax-calculator');

// Without Employment Allowance
const ni = calculateEmployerNI(35000);

// With Employment Allowance (£10,500 off)
const niEA = calculateEmployerNI(35000, { employmentAllowance: true });

calculateStudentLoan(grossSalary, options?)

Student loan repayments for all plan types.

const { calculateStudentLoan } = require('uk-tax-calculator');
const loan = calculateStudentLoan(40000, { studentLoan: 'plan2' });
console.log(loan.repayment);  // Annual repayment

calculateDividendTax(dividendIncome, otherIncome, options?)

Dividend tax considering £500 allowance and interaction with salary bands.

const { calculateDividendTax } = require('uk-tax-calculator');
const div = calculateDividendTax(15000, 40000);
console.log(div.tax);            // Tax on dividends
console.log(div.effectiveRate);  // Effective dividend tax rate %

calculateStampDuty(propertyPrice, options?)

SDLT (England), LBTT (Scotland) & LTT (Wales). Supports first-time buyer relief and additional property surcharge.

const { calculateStampDuty } = require('uk-tax-calculator');

// Standard purchase
const sd = calculateStampDuty(450000);

// First-time buyer
const ftb = calculateStampDuty(300000, { firstTimeBuyer: true });

// Second home in Scotland
const scot = calculateStampDuty(350000, {
  region: 'scotland',
  additionalProperty: true
});

Tax Year 2025/26 Rates

| Rate | Threshold | |------|-----------| | Personal Allowance | £12,570 | | Basic Rate (20%) | £12,571 – £50,270 | | Higher Rate (40%) | £50,271 – £125,140 | | Additional Rate (45%) | Over £125,140 | | Employee NI (8%) | £12,570 – £50,270 | | Employee NI (2%) | Over £50,270 | | Employer NI (15%) | Over £5,000 |

Full rates and thresholds at ukcalculator.com/2025-26-income-tax-bands-calculator

Links

• Interactive calculators: ukcalculator.com
• Salary Calculator: ukcalculator.com/salary-calculator
• Stamp Duty Calculator: ukcalculator.com/stamp-duty-calculator
• Employer NI Calculator: ukcalculator.com/employer-ni-calculator
• HMRC Official Rates: gov.uk/income-tax-rates

License

MIT — UKCalculator