Immigration, Refugees and Citizenship Canada (IRCC) has updated the process for international students who are applying for a Social Insurance Number (SIN) to work on-campus. As of February 10, 2017, international students no longer need an employment contract to apply for a SIN.
Previously, international students applying for a SIN to work on-campus were required to have a valid study permit and an employment contract. A SIN is required for all individuals who are eligible to work in Canada and are pursuing employment, whether on or off campus.
IRCC defines on-campus as "employment facilities within the boundaries of the campus" — for example, at a library, cafeteria, store, hospital, or research facility on the institution's campus. On-campus employment includes teaching and research assistant positions. International students who are studying full-time at a post-secondary institution may work without a work permit on the campus of their school, college, or university. The authorization to work applies for the duration of the study permit.
Full-time international students in Canada may also work off-campus while studying. In this case, a SIN is still required in order to begin working for an employer.