🔹 Social Insurance Number (SIN) in Canada A SIN is your key to working and accessing government services in Canada. It’s a unique 9-digit number required for: Employment: You must have a SIN to work in Canada. Taxation: Your employer uses it to report earnings to the government. Government Services: Access health care, benefits, and more. How to Apply: Eligibility: For Canadian citizens, permanent residents, and temporary residents. Documents: Submit proof of identity (passport, birth certifica