Lost SIN or identity theft in Canada: what to do

Service Canada no longer issues plastic SIN cards. If you know your number, you do not need to do anything about a missing card. To view your SIN, sign in to or register for My Service Canada Account. If you cannot remember it, check a tax return, a T4 or other tax slip, a Record of Employment or an RRSP contribution receipt (Service Canada, updated June 2, 2026).

If you still cannot find it, you can apply for a Confirmation of SIN. It follows the same process as a first-time application and needs the usual documents. It confirms your existing number and does not issue a new one.

Service Canada issues a new SIN only when there is clear evidence that your current number was used fraudulently. The page points to its "SIN fraud or data breach" guidance for next steps. A leaked number alone is usually handled by watching your credit and tax records, so keep reading the steps below.

• Fraud alerts and credit monitoring in Canada

These steps follow Community Legal Education Ontario and TransUnion Canada.

• File a police report and get a copy. Share it with banks, card issuers, credit bureaus and others.
• Contact affected businesses, such as banks and card issuers. You may need new account numbers, PINs and cards.
• Report to the Canadian Anti-Fraud Centre, 1-888-495-8501, for advice and help.
• Cancel and replace lost or stolen ID through the right agency: provincial ID, SIN or passport.
• Contact both Equifax and TransUnion. Ask for your credit reports, review them, dispute anything that is not yours and ask whether a fraud alert should go on your file.
• Keep a log of your calls, including the names of the people you spoke to. Follow up until each case is resolved.
• Get legal help if you need it, for example through a community legal clinic or a lawyer referral service.

Equifax says an alert applies only to your Equifax report, so contact TransUnion too. In Manitoba and Ontario, Equifax says lenders must call you before extending credit when an Identity Alert is in place; elsewhere in Canada they are only encouraged to. TransUnion says it does not charge to place or remove a credit freeze, which is a separate service.

• Do not share your SIN, birth date or banking details with people who contact you first. Scammers on romance, loan and job scams often ask for them.
• Use unique passphrases and multi-factor authentication.
• Check your credit report regularly. You can get it free.

• Cybersecurity basics
• Get your free credit report
• All scam types and red flags