where to find payroll number? On a payslip, you should be able to find that your payroll number is normally next to your name, employee ID, and National Insurance number. Alternatively, maybe your company’s HR software or employee portal has access to it. Your payroll or HR department can supply you with the number should you’ve misplaced your payslip. Payroll number helps your employer to follow the salary, tax and benefits. You will need it if you’re trying to resolve payroll issues or speaking to HMRC about your earnings and employment.