What is a Social Insurance Number (SIN)?

What is a SIN?

A social insurance number (SIN) is an identification given to eligible residents of Canada so that they can legally work, access government programs like the Canadian Pension Plan, and to keep track of tax reporting.

Service Canada issues SIN to Canadian citizens, permanent and temporary residents, and some refugee claimants.

All workers are legally obligated to provide their SIN to their employers when they start working for them.

Your SIN uniquely identifies you to the government, so it's important to know when you should share it, and when you should refuse to share it. 

Find out how to get a SIN.

When do I need to share my SIN?

You have to share your SIN when you:

• Get a job and your employer asks you for you SIN to pay you.
• Apply for government services (e.g., OSAP, Ontario Works, Child Tax Benefits, etc.).
• Complete your tax forms for work and file your taxes every year.
• Open a bank account that can accrue interest.

When should I refuse to share my SIN?

There are many situations where you are not required to share your SIN, even if you're asked. 

You have every right to refuse to share your SIN when you:

• Identify yourself. You only need to use your SIN for identification for government programs.
• Apply for a job. You don't have to provide employers with your SIN until you're hired.
• Apply to rent a home or sign a lease.
• Apply for a credit card.
• Make banking transactions. You do not need to provide your SIN to open a bank account if the account doesn't earn interest.
• Fill out medical paperwork.
• Rent a car.
• Apply for a college or university, although you will need a SIN to apply for government sponsored grants and loans.

How do I apply for a SIN?

There is no fee to apply for a SIN.

If you're over 12-years-old, and a Canadian citizen, or permanent or temporary resident, you can apply for your own SIN. Parents and guardians can apply for SIN on behalf of their children that are under 18-years-old in Ontario.

Start by reading this resource on how to get a SIN. Make sure you have all your required documents, then decide if you want to apply online, by mail, or in person at your local Service Canada centre.