The Social Insurance Number (SIN) is a nine-digit number issued by Service Canada that is required for any person working in Canada for pay, or receiving benefits under federal programs such as Employment Insurance (EI) and the Canada Pension Plan (CPP). Newcomers to Canada — whether permanent residents or temporary residents with work authorisation — must obtain a SIN before (or immediately upon) commencing employment. Temporary residents (work permit holders, study permit holders with work authorisation) receive a SIN that begins with the digit 9 and carries an expiry date that corresponds to the expiry of their immigration document. Permanent residents and citizens receive a SIN without an expiry date. Temporary residents can begin working as soon as they have applied for their SIN — they do not need to wait to receive the number. If a temporary resident has applied to extend their permit and is on maintained (implied) status, their SIN remains usable past its expiry date until a new permit is received and the SIN record is updated. This page explains the SIN application process for newcomers, the 9-series SIN system, the implied status rule, and the obligation to protect the SIN as sensitive personal information.

For current SIN application requirements, forms, and documentation for temporary residents, refer to the Service Canada SIN for temporary residents page.

• Department of Employment and Social Development Act, s 28.1 — establishes the Social Insurance Register and the authority of the Minister of Employment and Social Development to assign SINs
• Social Insurance Number Code of Practice — ESDC's code governing when SINs may be collected, used, and disclosed; establishes that SINs are confidential and sensitive personal information; limits who may request a SIN (canada.ca/sin-code-of-practice)
• Income Tax Act — requires employers to collect and use the SIN to administer payroll deductions and T4 reporting; employees are required to provide their SIN to their employer
• Employment Insurance Act and Canada Pension Plan — require the SIN for administering EI premiums and CPP contributions
• Service Canada: SIN for temporary residents — canada.ca/sin-temporary-residents

Who needs a SIN and when

The following persons in Canada need a SIN:

• Anyone working for pay in Canada: all employees must provide their SIN to their employer; employers use the SIN to process T4 slips, payroll deductions, and government program contributions
• Anyone applying for or receiving government benefits: EI, CPP, Old Age Security (OAS), and certain provincial benefit programs require a SIN
• Certain financial account holders: banks and financial institutions may request the SIN for interest income reporting to the Canada Revenue Agency (CRA)

Temporary residents who hold a work permit authorising them to work in Canada should apply for their SIN as soon as possible after arriving — before or at the time they start work.

Who is eligible to apply for a SIN as a temporary resident

To apply for a SIN as a temporary resident, the person must hold one of the following documents that authorises them to work in Canada:

• A work permit that includes the statement "may work" or "may accept employment" in Canada (whether employer-specific or open)
• A visitor record that authorises work (issued in certain circumstances)
• A study permit that authorises on-campus work, or that is accompanied by a work permit authorising work off-campus
• A diplomatic identity card with work authorisation issued by Global Affairs Canada

Persons who hold only a visitor visa or entry stamp (with no work authorisation) are not eligible to apply for a SIN and cannot work in Canada without obtaining work authorisation first.

The 9-series SIN and expiry date

Temporary residents receive a 9-series SIN — a SIN that begins with the number 9. This distinguishes their SIN from the SINs issued to permanent residents and citizens (which begin with 1 through 8). Key features of the 9-series SIN:

• The SIN has an expiry date equal to the expiry date of the immigration document that authorised the work (for example, the work permit expiry date)
• When the temporary resident obtains a new immigration document (e.g., a renewed work permit), they must update their SIN record with Service Canada to extend the SIN expiry date to match the new document
• A SIN that has expired cannot generally be used to start a new job — but see below for the implied status exception
• Permanent residents, upon receiving their first permanent resident document, should apply for a new SIN without an expiry date (or update their existing SIN to remove the expiry)

Applying for a SIN — process and documents

There are three ways to apply for a SIN:

• Online: the fastest option; the SIN confirmation letter is available through My Service Canada Account (MSCA) in approximately 5 business days; or it is mailed within 5 business days of verification
• In person at a Service Canada office: the SIN is provided immediately at some offices if all required documents are presented; this is the fastest option for those who need the SIN number immediately
• By mail: takes approximately 20 business days from receipt of the application

The required documents for a temporary resident SIN application include the valid immigration document authorising work (work permit or equivalent) and proof of identity. For the current document checklist, refer to the Service Canada SIN required documents page.

Can start working before receiving the SIN

A temporary resident who has applied for their SIN does not need to wait to receive the SIN number before starting work. Service Canada confirms that a person may begin working as soon as the SIN application has been submitted. The SIN number must be provided to the employer within a reasonable time after it is issued. If an employer requires the SIN number before allowing work to begin, the applicant can show confirmation of the SIN application as evidence of the pending number.

Implied status and expired SIN

When a temporary resident's work permit expires while an extension application is pending with IRCC, the person is on implied (maintained) status — they remain authorised to work in Canada while IRCC decides the renewal application. For details on implied status, see the implied status page. The SIN implication of implied status:

• If the SIN expiry date has passed (because the work permit has expired), the temporary resident on implied status can continue to use their expired SIN for employment during the implied status period
• Once IRCC issues the new work permit, the person must apply to Service Canada with the new immigration document to update the SIN expiry date
• Employers who request the SIN should be informed that the expiry date on the SIN may not reflect the current period of authorisation while the renewal is pending

Protecting the SIN — confidentiality and misuse

The SIN is sensitive personal information and should be protected carefully:

• The SIN should only be shared with those who have a legal right to ask for it — primarily employers (for payroll and T4 purposes) and government agencies administering programs that require a SIN
• Banks and financial institutions may request the SIN for interest income reporting, but are not legally required to do so for opening accounts
• Landlords, employers for non-payroll purposes, and other private parties do not have a legal right to collect the SIN — the SIN Code of Practice limits who may collect and use SINs
• Identity theft involving the SIN is a serious risk — a stolen SIN can be used to file fraudulent tax returns, make fraudulent benefit claims, and access financial services in the holder's name

The SIN is one of the first practical steps for any newcomer who plans to work in Canada — it is needed on day one of employment and employers are legally required to collect it for payroll. The 9-series SIN system means that temporary residents' work authorisation is effectively flagged by the SIN digit, and the expiry date creates an administrative obligation to update Service Canada whenever a permit is renewed. Many temporary residents are unaware that they can begin working as soon as they have applied — waiting to receive the SIN number (which may take days by mail) before starting work is unnecessarily cautious. The implied status SIN rule is particularly important for workers who are renewing their permits — their continued right to work exists even after both the permit and the SIN technically show as expired, but employers may not be aware of this. Permanent residents should update their SIN record as soon as they receive their permanent resident documentation to remove the expiry date from their SIN. For current SIN application requirements, processing times, and the implied status guidance, refer to the Service Canada SIN for temporary residents page.