Do your social insurance numbers (SIN) remain active after you leave?

A Social Insurance Number (SIN) is a vital identifier for anyone working or living in Canada. Many Ukrainian immigrants and other residents of the country are wondering: what happens to their SIN after they leave Canada? Does it remain valid? Can it be reinstated upon return? There are no simple answers to these questions, as everything depends on several key factors.

Differences between different types of SIN

SIN for citizens and permanent residents

If you are a Canadian citizen or permanent resident, your SIN never expires or becomes invalid. This number stays with you for life, regardless of where you live. SINs for citizens and permanent residents do not start with the number “9” and do not have an expiry date.

Even if you live abroad for many years, your SIN as a citizen or permanent resident technically remains valid. However, there is an important caveat: it may become “inactive” or “dormant” after a long period of inactivity.

SIN for temporary residents

The situation is completely different for temporary residents. A SIN starting with the number “9” is issued to individuals who are not citizens or permanent residents of Canada. These numbers have a limited validity period and automatically expire when your work or study permit expires.

If you have a temporary SIN (beginning with “9”) and leave Canada after your permit expires, that number simply becomes invalid. When you return to Canada with new documents, you will need to apply to renew or obtain a new SIN.

The concept of an “inactive” SIN

What does “inactive” status mean?

The most important thing to understand is that even for citizens and permanent residents, a SIN can become ‘inactive’ or “dormant” after five years of no activity. This means that if you have not filed tax returns, worked in Canada, or used your SIN to access government services for five years, the system may mark your number as inactive.

It is important to understand that inactive status does not mean that you lose your number or your rights. It is more of a protective measure against fraud. As one source notes: “Your inactive SIN does not prevent you from returning to Canada and rebuilding your life here.”

Practical implications of inactive status

With an inactive SIN, you can still do most of the basic things when you return to Canada:

  • apply for jobs
  • open bank accounts
  • obtain a driver's license
  • register with the health care system

However, you will not be able to use online government services such as My Service Canada Account until you reactivate your number. Employers may be notified that your SIN is not a valid number, even though you are technically eligible to work. This can cause inconvenience, so it is recommended that you reactivate your number as soon as possible after your return.

SIN reactivation process

Required documents and procedure

To reactivate an inactive SIN, you must visit a Service Canada office in person. The procedure involves filling out a special questionnaire from the SIN registry and providing documents that prove your identity.

Citizens and permanent residents must provide documents such as:

  • Canadian birth certificate
  • Citizenship certificate or permanent resident card

Service Canada staff will conduct an interview to confirm your identity and the circumstances of your absence.

Processing times

Exact reactivation times can vary. Some individuals report quick processing within a few days, while others wait several weeks. It is recommended that you contact Service Canada as soon as possible after your return, especially if you already have a job offer.

Impact on pension contributions and benefits

Preservation of CPP contributions

One of the most important aspects is that your contributions to the Canadian Pension Plan (CPP) are not lost while you are away from Canada. Even with an inactive SIN, you can apply for CPP benefits when you reach the eligible age.

Your previous contributions are credited regardless of where you currently live. Many Canadians successfully receive CPP benefits while living abroad. You will need your SIN to access information about your contributions and apply for a pension.

Tax implications

It is important to understand the difference between your SIN status and your tax residency status. Even if your SIN remains technically valid, you may lose your Canadian tax residency status if you sever all substantial ties to the country.

If you plan to leave Canada permanently, it is recommended that you file Form NR73 with the Canada Revenue Agency to determine your residency status. This will help you avoid double taxation and determine your tax obligations.

Loss of permanent resident status

Impact on your SIN when you lose your PR status

If you lose your permanent resident status due to failure to meet residency requirements or other reasons, your SIN may change. Technically, if your PR status has been officially revoked, using your previous SIN becomes illegal.

In this situation, you must notify Service Canada of your status change and return your SIN. When you return to Canada as a visitor, you can apply for a new temporary SIN (beginning with “9”) if you obtain a work permit.

Restoring PR status

If you later restore your permanent resident status, you can apply for a new permanent SIN. It is important to note that your SIN does not automatically expire when your PR card expires—the card and status are two different things.

Recommendations for different scenarios

For Canadian citizens

  • Write down your SIN in a safe place
  • Consider filing a form to change your resident status for tax purposes
  • Be prepared to reactivate your number when you return after a long absence
  • Remember that you will be eligible for CPP pension benefits regardless of where you live

For permanent residents

  • Keep track of the time spent outside Canada to comply with PR status requirements
  • Understand that your SIN remains valid even after your PR card expires
  • Prepare documents for possible reactivation upon return
  • Keep documents confirming your PR status

For temporary residents

  • Your SIN will automatically expire when your work or study permit expires

  • You will need to apply for a new SIN upon your return

  • CPP contributions made while working remain valid for future pension benefits

  • It is important to keep records of your employment in Canada for future pension claims

SIN Protection and Security

Importance of Confidentiality

Regardless of your status in Canada or your plans to leave, protecting your SIN remains critically important. This number contains sensitive personal information and should only be used for authorized purposes.

Never use your SIN as a form of identification for things such as renting a place to live or applying for a job (before you have received an offer). Employers can only ask for your SIN after they have hired you.

Fraud and protection

Be cautious of fraudulent calls or emails asking for your SIN. The Government of Canada never contacts citizens unexpectedly to request personal information. If you receive a suspicious request, verify its authenticity through official government channels.

Conclusions

The SIN is a reliable long-term identifier for Canadian citizens and permanent residents, which remains valid even after extended periods of living abroad. Although the number may become inactive after five years of non-use, it can be easily reactivated upon returning to Canada.

For temporary residents, the situation is different: their SINs automatically expire when their residence permits expire. However, all contributions to Canadian social programs are retained and can be used to obtain future benefits.

It is essential to understand the difference between your immigration status, SIN status, and tax resident status. Each of these aspects has its own rules and requirements that may affect your rights and obligations both before and after you leave Canada.

If you are planning to leave Canada or already live abroad, it is recommended that you consult with qualified immigration and tax professionals to understand all the implications of your specific situation.