Employer SIN checklist: collect, check and protect.

The checklist

• Ask for the SIN within 3 days of the start date.
  CRA: get the SIN within 3 days of when the employee starts. Service Canada: request it within three days after the day employment begins.
• Record the dates and way you asked.
  CRA: show a reasonable effort; keep notes of dates you asked verbally and copies of written requests.
• If the employee has no SIN yet, ask them to apply and give it to you within 3 days of receiving it.
  CRA
• If they did not give a SIN, tell Service Canada within 6 days of the start date.
  CRA
• Still make payroll deductions, and report them on the T4 by the last day of February of the next year.
  CRA
• If the SIN starts with 9, check the immigration document and its expiry date.
  Service Canada and CRA: the 9-series is valid only until the expiry date on the IRCC document.
• If the document has expired, ask the employee to contact IRCC for a valid one.
  CRA and Service Canada
• Check the number itself for typos with a format and Luhn check.
  Optional. This catches typing errors only, it does not confirm the SIN was issued.
• Confirm the SIN with Service Canada if you need to.
  Service Canada says an employer can confirm the SIN of a current or former employee by contacting Service Canada, and will need to give the business number the CRA issued along with identifying information.
• Store the SIN securely and use it only for income-related information.
  Service Canada: SINs are confidential; store personal information in a secure area or on an encrypted system.
• Do not treat a SIN card or confirmation letter as identification.
  Service Canada: neither is an identity document.

Penalties and accuracy

The CRA says a $100 penalty may apply if the employer failed to show reasonable attempts to obtain a SIN, and a $100 penalty may apply to an employee who failed to provide it when required, unless the employee applies for a SIN within 15 days of the request and gives it to the employer within 15 days of receiving it. It also notes an incorrect SIN can affect an employee’s future Canada Pension Plan benefits, which is the reason to catch typos early. The SIN validator does that check, and this guide explains how.

Temporary 9-series SINs

Numbers that begin with 9 belong to temporary residents and are valid only until the expiry date on the immigration document. Use the temporary SIN checker to spot them, then verify the document, not the number.

Keep it confidential

See the SIN privacy guide for the Service Canada rules on when a SIN may be requested.

This checklist summarizes the linked government pages as read in October 2026. Rules change, so confirm against them, and ask a payroll professional about your situation.

Frequently asked questions

How long does an employer have to get an employee’s SIN?

The CRA says to get the SIN from the employee within 3 days of when they start work. Service Canada says to request it within three days after the day employment begins.

What if the employee does not give me their SIN?

The CRA says to show a reasonable effort to get it, to inform Service Canada within 6 days of the start date, and still to make deductions and report them on the T4.

How do I verify an employee’s SIN?

You can check the digits for typing errors, which does not prove the SIN was issued. Service Canada says an employer can confirm the SIN of a current or former employee by contacting Service Canada.

What do I do with a SIN that starts with 9?

It is a temporary SIN. Ask to see the immigration document and check that it has not expired, because the SIN is valid only until the expiry date shown on it.

Is a SIN card proof of identity?

No. Service Canada says neither the SIN card nor the confirmation of SIN letter is an identity document.

Sources (retrieved October 2026): CRA: Get the SIN from the employee; Service Canada: Employer information, SIN; Service Canada: SIN for temporary residents. TNAADO is not affiliated with the Government of Canada; this page is general information, not legal or immigration advice.