Northern Ireland Second Job Calculator

How Your Second Job Is Taxed in Northern Ireland

Taking on a second job in Northern Ireland affects your tax because HMRC assumes your personal allowance is already used in your primary role. This calculator helps you estimate your take-home pay from a second job for the 2024/25 tax year, accounting for income tax, National Insurance, pensions, and student loan repayments.

PAYE and Second Job Tax Codes

When you have two jobs, HMRC typically applies one of the following flat-rate tax codes to your second income:

- **BR (Basic Rate):** All income taxed at 20%

- **D0 (Higher Rate):** All income taxed at 40%

- **D1 (Additional Rate):** All income taxed at 45%

These codes do not include any personal allowance. This avoids overuse of your tax-free entitlement across both jobs. Your employer selects the appropriate code based on HMRC instructions, and the calculator allows you to choose the one applied to your second role.

National Insurance Contributions (NICs)

NICs are assessed independently for each job. If your second job earnings exceed the monthly threshold, you will owe Class 1 NICs at 8% on earnings up to the Upper Earnings Limit. Even modest additional earnings can trigger National Insurance. Our calculator accounts for these deductions.

Pension Contributions

If you’re automatically enrolled in a pension at your second job, contributions are deducted from your pay and reduce your taxable income. The calculator allows you to enter a pension rate to estimate the impact on your net salary.

Student Loan Repayments

If you’re repaying a student loan, deductions may be made from both jobs once income exceeds your repayment threshold. Each employer calculates repayments independently, which may result in overpayments. HMRC reconciles this at year-end. The calculator estimates repayments from the second job only.

Use Cases

This calculator is ideal for workers in Northern Ireland juggling multiple part-time roles, freelance work, or side gigs. It helps you understand how income tax, NI, pensions, and loan repayments reduce your second job income—before year-end reconciliation by HMRC.

Use this tool to make informed decisions about how much extra work will realistically boost your take-home pay.