Yourtax office reference number on payslip (also known as the PAYE reference) and it tends to be under the heading ‘Tax Ref’, ‘Employer PAYE Reference’, or something similar. Often it is shown near your National Insurance number and tax code. This number is especially important for HMRC to get the correct tax and National Insurance payments. You might also want to use it while changing jobs, making demands from your employer, filling in the tax returns or when demanding your tax refund. In case they are not included in your payslip, contact your HR or payroll department.