What is a Social Insurance Number?

Your social insurance number (SIN) is a unique 9-digit number that lets you work in Canada and access government programs and benefits (like the Canada Pension Plan, Employment Insurance program, or Canada Student Loans). Your SIN is formatted in groups of three digits (such as 234-567-890) and can be found on:

  • Your confirmation of SIN letter or valid SIN card issued by Service Canada
  • The first page of your previous year’s Canadian tax return or
  • Your notice of assessment or reassessment from the Canada Revenue Agency (CRA) or Revenu Québec

Remember, to successfully file your taxes, you’ll need to enter your SIN on your tax return – it is your main identifier with the CRA (and Revenu Québec, if applicable).