Fact Sheets

Social Insurance Number (SIN)

What is the Social Insurance Number (SIN)?

The SIN was created in 1964 to serve as a client account number in the administration of the Canada Pension Plan and Canada's varied employment insurance programs. In 1967, what is now Canada Revenue Agency (CRA) started using the SIN for tax reporting purposes.

Why do organizations ask for it?

Organizations in and outside government ask for the SIN because it is a simple method of identification. Many use it as a client account number to save them from setting up their own numbering systems.

Although only certain government departments and programs are authorized to collect and use the SIN, there is no legislation that prohibits organizations asking for it.

Why is my SIN so important to personal information and privacy?

  • The SIN may be a key piece of information to open the door to your personal information.
  • Computer technology makes it possible to use the SIN to find and match your information from one database to another; without your knowledge, a detailed profile could be drawn about you. This amounts to "data surveillance" or monitoring of your daily life, which can pose a serious threat to our privacy and autonomy.
  • Your SIN can be used to steal your identity. Along with other personal information, someone may be able to use your SIN to apply for a credit card or open a bank account, rent vehicles, equipment, or accommodation in your name, leaving you responsible for the bills, charges, bad cheques, and taxes.

Who can ask for my SIN?

Your SIN is a confidential number that is restricted to income reporting purposes. There are a select and limited number of federal government departments and programs specifically authorized to collect the SIN. See list below.

The authority to collect and use the SIN is tied to a specific legislated purpose, not necessarily to a particular body. For example, an employer can collect an employee's SIN to provide them with Records of Employment and T-4 slips for income tax purposes, as can provincial or municipal agencies to report financial assistance payments for income tax purposes.

Institutions from which you earn interest or income, such as banks, credit unions and trust companies, must also ask for your SIN.

So, what can I do when asked for my SIN?

  • Ask if you are required by law to provide it (see list below);
  • Ask why the person needs it, how it will be used and to whom it will be given;
  • Your SIN is not a piece of identification. If it is not required by law (and you are not satisfied with the explanation), tell the person you prefer not to use the SIN and offer other identification;
  • If the organization refuses to give you the product or service unless you give your SIN, complain to the Privacy Commissioner of Canada;
  • If you would like better legal protection for your SIN, call or write your federal Member of Parliament.

Do any provincial and municipal safeguards exist?

While most provincial and municipal governments may not be prohibited from collecting and using the SIN, many are reviewing their use of it and considering alternatives. All provinces and territories have privacy laws to protect personal information in government files.

If you are concerned about how your provincial government is using the SIN, contact your provincial information and privacy commissioner and find out more.

How am I protected in the private sector?

The Personal Information Protection and Electronic Documents Act (PIPEDA) sets out ground rules for how private sector organizations may collect, use or disclose personal information in the course of commercial activities.

Since January 1, 2001, the Act applied to personal information about customers or employees that is collected, used or disclosed by the federally-regulated sector in the course of commercial activities. It also applies to information that is sold across provincial and territorial boundaries. As of January 1, 2004, the Act covers the collection, use and disclosure of personal information in the course of any commercial activity within a province, including provincially-regulated organizations, except in provinces that have enacted legislation that is deemed to be substantially similar to the federal law.

Under the new law, organizations like banks, telecommunications companies and airlines cannot require you to consent to the collection, use or disclosure of your personal information unless it is required for a specific and legitimate purpose.

This means that unless an organization can demonstrate that your SIN is required by law, or that no alternative identifier would suffice to complete the transaction, you cannot be denied a product or service on the grounds of your refusal to provide your SIN.

If you disagree with a request for your SIN made by an organization that is subject to the PIPEDA, you can complain to the Privacy Commissioner of Canada, who will investigate the complaint.

Legislated uses of the SIN (or legislation that regulates its use) include:

  • Canada Pension Plan, Old Age Security and Employment Insurance contributions or claims (the original purposes for the SIN);
  • Income Tax identification;
  • banks, trust companies, caisse populaires and stock brokers when they sell you financial products (GICs or Canada Savings Bonds) or services (bank accounts) that generate interest. They declare your interest to Canada Revenue Agency (CRA) for income tax purposes;
  • various Veterans Affairs benefit programs;
  • Canada Student Loans or Canada Student Financial Assistance;
  • Canada Education Savings Grants;
  • Gasoline and Aviation Gasoline Excise Tax Applications;
  • Canadian Wheat Board Act;
  • Labour Adjustment Benefits Act;
  • Tax Rebate Discounting Regulations;
  • Race Track Supervision Regulations;
  • Garnishment Regulations (Family Orders and Agreements Enforcement Assistance Act);
  • Canada Elections Act;
  • Canadian Labour Standards Regulations (Canada Labour Code);
  • Farm Income Protection.

Programs Authorized to use the SIN:

  • Immigration Adjustment Assistance Program;
  • Income and Health Care Programs;
  • Income Tax Appeals and Adverse Decisions;
  • Labour Adjustment Review Board;
  • National Dose Registry for Occupational Exposures to Radiation;
  • Rural and Native Housing Program;
  • Social Assistance and Economic Development Program

For more information about privacy and your SIN, call toll free 1-800-282-1376, or write:

The Office of the Privacy Commissioner of Canada
30 Victoria Street
Gatineau, Quebec
K1A 1H3

Visit the Service Canada Web site to find answers to general questions about the SIN - such as how to apply for a SIN, or replace a lost or stolen card.