How Do I Apply for a SIN in Canada?
A Social Insurance Number, or SIN, is a nine-digit number used for working in Canada and accessing government programs and benefits. Service Canada, not the CRA, manages SIN applications.
You can apply online, by mail or in person depending on your situation.
Documents you need
Service Canada says applicants need a primary identity document that proves status in Canada and a secondary identity document. If your name is different from the primary document, supporting documents may also be needed.
Applying online
The online SIN application requires digital copies of the required documents. Service Canada says applications are processed after submission and a response is provided by mail. If you need a SIN urgently, Service Canada recommends applying in person.
Protect your SIN
A SIN is sensitive personal information. Do not use it as general identification or provide it when there is no legal or administrative need. Be careful with unsolicited requests by phone, text or email.
Why a SIN matters for taxes
Employers use the SIN for payroll reporting, and the CRA uses it to connect tax returns and benefit information to the correct taxpayer. Make sure the name and identity information on your tax records is consistent.
FAQ
Can GROWS Financial issue a SIN?
No. SINs are issued by Service Canada.
Can I apply online?
Yes, if you can provide the required digital documents.
Should I carry my SIN document with me?
No. Protect the number and only provide it when it is required.
Call to action
Once you have a SIN and need help with your first Canadian tax return, GROWS Financial can help organize the tax filing side.
Related services: Personal Tax.
Related reading: I Just Moved to Canada. Do I Need to File a Tax Return?
Official sources for fact-checking
Last reviewed: October 21, 2026.