How Do I Know If Someone Is Using My SIN?

How Do I Know If Someone Is Using My SIN?

Written by Matthew Taylor
Fact-checked by Caitlin Wood
Last Updated September 9, 2022

A Social Insurance Number (SIN) allows you to work in Canada, file taxes, and have access to government programs and benefits. It is extremely important that you protect your SIN. Not being vigilant may require you to get a new SIN, which is a lengthy process during which it will be more difficult to access programs or do any of the activities that require a SIN, like starting a new job.

Check out these tax benefits for parents.

What Is A Social Insurance Number? 

A SIN is a 9-digit number issued by the Government of Canada to an individual living in Canada. This number allows you to work in Canada, access government programs and benefits, and file taxes. Because a SIN is issued to a specific person, it is illegal for another person to use it. Any fraudulent activity done with a SIN can be hard to undo and may require you to request a new SIN.

Find out how to tell if you’ve been a victim of identity theft.

What Happens If Someone Gets Their Hands On Your SIN?

Because a SIN is required for you to access some government programs and financial benefits, if your SIN is compromised, someone else may gain access to these things instead of you. You might also become the victim of identity theft and other kinds of fraud because fraudsters may get access to your personal information.

If your SIN is being used for fraudulent purposes, it  can take a long time to get your credit rating back on par. This is because fraudsters apply for loans and credit cards in your name, but since these are not in the fraudster’s name they have no intention of paying them back. As such, you’ll  be on the hook to pay these back, and your credit may be negatively affected for each debt payment they miss.

If someone else has access to your SIN, they might be claiming income and other benefits that you did not receive. You would be on the hook to pay taxes to the Canada Revenue Agency on income that you did not earn or receive.

Find out what you can do if you can’t pay your taxes.

How Do You Know If Someone Is Using Your SIN?

There are several ways to tell if someone is using your SIN.

Tax Information From The CRA

If the Canada Revenue Agency sends you a Notice of Reassessment for undeclared earnings, that means that someone used your SIN to receive taxable income. You would be on the hook for paying the taxes on this income even though you did not receive it yourself.

Check out what happens if you’re being audited by the CRA.

Checking Your Credit Report

Checking your credit report is another good way to see if someone is fraudulently using your SIN. If you see a credit account that you did not open, that’s a good sign that someone has used your SIN to open a new account. 

Lookout Is Credit Monitoring A Good Way To Protect Your Identity?

Loans Canada Lookout


You Stop Receiving Bills

You might also stop receiving your bills and financial statements. This could mean that your accounts have been cancelled, or that your mail has been redirected. Either way, it’s a cause for concern.

Finally, seeing transactions in your bank account that you didn’t make is a good sign that there’s some suspicious activity going on. The more frequently you check your account, the sooner you can catch any potential fraud.

Learn what you should do if you don’t recognize a charge on your account.

What To Do If Someone Is Using Your SIN

If someone is using your SIN, you should file a report with the police and with the Canadian Anti-Fraud Centre. They can help you to limit the damage caused by someone else using your SIN.

You should also start to control the damage yourself. Change any passwords, especially those for financial or government institutions, so only you can access sensitive information. Review your credit reports and place a credit fraud alert so you can identify fraudulent activities. Also review your bank activity and your mail to see if any suspicious transactions are being made.

You should also visit Service Canada to start the process of getting a new SIN. You should bring your old SIN card (if possible) and either a birth certificate, a Certificate of Canadian Citizenship, or a Certificate of Indian Status. These documents will be used to prove your identity.

Here are common errors you should check for on your credit report

How To Protect Your SIN

One of the best ways to protect your SIN is to keep your SIN card safe. This means keeping it in a secure place you won’t lose it. Never carry your SIN card because it makes it easier for you to lose it or for it to be stolen.

You should also only provide your SIN when you are legally obligated to and in a safe way. For example, it is perfectly legal for an employer to ask for your SIN for tax purposes or to set up payroll. You shouldn’t use it, for example, to prove your identity, and you shouldn’t send it over email.

If someone does actually get access to your SIN when they shouldn’t, take action if you either suspect fraud or when you can confirm it. Limit the damage by reporting the fraud as soon as you can and take steps to get a new SIN.

Frequently Asked Questions

Can I get a new SIN if mine has been compromised? 

Yes, you can. You will have to go through the proper steps with Service Canada to get a new SIN. You must prove that your old SIN was used fraudulently.

When am I obligated to provide my SIN?

You are obligated to provide your SIN to access some government programs and services such as the Canada Pension Plan (CPP) and Employment Insurance (EI). You also have to provide it to your employer so you can be charged income tax and so you can receive benefits. If you have an account that pays interest at a financial institution, you must also provide your SIN. You can choose when and with whom to share your SIN. If someone wants you to provide your SIN and you’re suspicious, look into it to make sure that everything is above board.

Does getting a new SIN protect me from identity theft?

No. Just because you get a new SIN, it doesn’t mean you’re in the clear. You’re not free from fraud or identity theft. You may have to prove that you weren’t involved in any fraud with your old SIN, and you may need to pay off the debts incurred by whoever stole your SIN.

What should I do if my information is leaked due to a data breach?

If your information is leaked due to a data breach, you should contact Canada’s two major credit bureaus (Equifax and TransUnion) to monitor your credit file. If you see something suspicious, report it and take action to protect yourself. This means changing your passwords, asking creditors about suspicious transactions, and maybe even getting a new SIN. If you look at your financial statements regularly, you have a much better chance of limiting any damage caused by a data breach. You will be able to pinpoint any suspicious activity, which you should report to the police, the Canadian Anti-Fraud Centre, and Service Canada.

Bottom Line

You must keep your SIN safe at all times to protect yourself. If you don’t, you may become the victim of identity theft and other kinds of fraud. Even if you get a new SIN, you may still be on the hook for any damage caused by the fraudulent use of your SIN. If you remain vigilant, you should have no problem with SIN fraud.

Rating of 5/5 based on 11 votes.

Matthew joined the Loans Canada writing team in 2021 while was finishing up a Bachelor's degree at the University of Saskatchewan. It was there that he discovered his love of writing. His work has appeared in several publications, including the Canadian Student Review and In his spare time, Matthew enjoys reading, geocaching, and spending time with his family and pets.

Click on the star to rate it!

How useful was this post?

Research & Compare

Canada's Loan Comparison Platform

Largest Lender Network In Canada

Save time and money with Loans Canada. Research and compare lenders before you apply. Share your experiences with Canada's top lenders.

Save With Loans Canada

Special Offers

Up to $1,500 Cash Back

Up to $1,500 Cash Back
Mortgage offer

Frank Mortgage is Canada’s one-stop shop for mortgages. Get up to $1,500 cash back on your mortgage.

View Offer
Improve Your Credit With Fidem

Improve Your Credit With Fidem

Great unsecured credit card for customers currently in, or recently discharged from, a consumer proposal or bankruptcy

View Offer
Earn 5% Cashback With Neo

Earn 5% Cashback With Neo
No annual fee!

Earn an average 5%¹ cashback at thousands of partners and at least 0.5%² cashback guaranteed with Neo.

View Offer
Build Credit For $10/Month

Build Credit For $10/Month

KOHO’s Credit Building Program helps you build a better credit history with easy to manage payments for just $10/month.

View Offer
Best Personal Loan Provider by Greedy Rates

Confidential & risk-free

All consultations and conversations with Loans Canada and its partners are confidential and risk-free. Speak with a trusted specialist today and see how we can help you achieve your financial goals faster. Loans Canada and its partners will never ask you for an upfront fee, deposit or insurance payments on a loan. Loans Canada is not a mortgage broker and does not arrange mortgage loans or any other type of financial service.

When you apply for a Loans Canada service, our website simply refers your request to qualified third party providers who can assist you with your search. Loans Canada may receive compensation from the offers shown on its website.

Only provide your information to trusted sources and be aware of online phishing scams and the risks associated with them, including identity theft and financial loss. Nothing on this website constitutes professional and/or financial advice.

Your data is protected and your connection is encrypted.

Loans Canada Services Are 100% Free. Disclaimer

Build Credit For Just $10/Month

With KOHO's prepaid card you can build a better credit score for just $10/month.