A Social Insurance Number (SIN) is a nine-digit number that you need to work in Canada or to have access to government programs and benefits. It is a confidential number and you are responsible for protecting it from unauthorized use. The Government of Canada issues SINs in a paper format called a SIN Confirmation, as plastic SIN cards are no longer issued.
You can apply for a SIN online, by mail, or in person at a Service Canada Centre. To apply, you must provide a valid primary document that proves your identity and legal status in Canada, such as a birth certificate, a permanent resident card, or a work or study permit. If the name on your primary document is different from the name you are currently using, you must also provide a supporting document.
Anyone who wants to work in Canada or receive benefits and services from government programs must have a SIN. This includes Canadian citizens, permanent residents, and temporary residents. Parents and legal guardians can also apply for a SIN for children under the age of majority in their province or territory. If you are a temporary resident, your SIN will start with the digit "9" and will have an expiry date that matches the expiry date on your immigration document.
Your SIN is used by various government departments and agencies to identify you for tax purposes and benefit administration. Because it is a key piece of personal information, you should only provide it when it is legally required, such as to your employer after you have been hired, to your financial institution for interest-bearing accounts, or when applying for government benefits. Be cautious of any requests for your SIN over the phone or by email, and report any suspected identity theft or fraudulent use of your number immediately.
If your SIN confirmation is lost or stolen, Service Canada will not issue a new SIN unless there is proof that it was used fraudulently. Instead, you can request a confirmation of your existing SIN by providing the same identity documents required for an initial application. If you have evidence that someone else is using your SIN, you should contact the police and the Canadian Anti-Fraud Centre before applying for a new number.