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Who Can ask for my SIN number?
Your Social Insurance Number (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.
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 employees 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.
If you live in Quebec, Hydro Québec is required by provincial law to collect a SIN for opening new accounts.
You are not required to provide your SIN number to any other private-sector organization or person such as a landlord. There is no law preventing private-sector organizations from asking for the SIN for other purposes, such as identification, but they do need to make people aware that collection of a SIN is optional and not a condition of service.
Our Office recommends that no private-sector organization request the SIN from a customer, and that no customer give the SIN to a private-sector organization, unless the organization is required by law to request it.
Any organization that collects your SIN, whether it operates under PIPEDA or the public-sector Privacy Act, a must do so under strict rules to protect your privacy."
https://www.priv.gc.ca/faqs/index_e.asp#q012
"What information can a prospective landlord ask me for?
In order to make a decision on whether or not to rent a property to you, a prospective landlord may ask for some personal information that will allow them to complete a credit check. A credit check will give the prospective landlord information about your ability to pay the rent and the potential timeliness of your payment. A prospective landlord is required to gain your consent to share your personal information with any third party or organization, such as a credit reporting agency for a credit check.
Information that is required in order to run a credit check is as little as your name, address and date of birth. Although not necessary for a credit check, your drivers license, passport, employer, income and expenses may be asked for on your rental application which may allow your landlord to obtain a more detailed report from organizations that offer credit checks.
You are not required to provide your SIN number to any private-sector organization or person such as a landlord. There is no law preventing private-sector organizations from asking for a SIN for other purposes, such as identification, but they do need to make people aware that collection of a SIN is optional and not a condition of service.
There is also nothing in the law that limits landlords from asking for your drivers license or passport. These two forms of identification are unique to you and they contain a significant amount of personal information such as your name, address, picture, some physical descriptions, signature, possibly your year of birth and location; and, gender. Be aware of the reasons behind why someone would be asking you for this information and consult with their privacy policy or privacy officer if you have any questions.
Sometimes a prospective landlord may only ask to view these documents as opposed to copying or writing down the information. This is usually done to verify or confirm the information you have already provided to them and can help to safeguard this sensitive personal information.
Once an organization or landlord has collected any personal information, it takes on new risks and responsibilities under PIPEDA. PIPEDA requires any private organization that collects your personal information to also protect it against unauthorized loss, theft or disclosure. Because credit bureauswhich are used by many landlordscollect, use and disclose personal information through their consumer credit reports, they are also governed by provincial and federal privacy laws.
You are entitled to see your personal information that is in the hands of an organization covered by the Act. You are also entitled to challenge the accuracy and completeness of the personal information, and to have it amended as appropriate."