Before You Co-Sign a Mortgage

Tim Lyon • April 24, 2025

So you’re thinking about co-signing on a mortgage? Great, let’s talk about what that looks like. Although it’s nice to be in a position to help someone qualify for a mortgage, it’s not a decision that you should make lightly. Co-signing a mortgage could have a significant impact on your financial future. Here are some things to consider.


You’re fully responsible for the mortgage.


Regardless if you’re the principal borrower, co-borrower, or co-signor, if your name is on the mortgage, you are 100% responsible for the debt of the mortgage. Although the term co-signor makes it sound like you’re somehow removed from the actual mortgage, you have all the same legal obligations as everyone else on the mortgage. When you co-sign for a mortgage, you guarantee that the mortgage payments will be made, even if you aren’t the one making them.


So, if the primary applicant cannot make the payments for whatever reason, you’ll be expected to make them on their behalf. If payments aren’t made, and the mortgage goes into default, the lender will take legal action. This could negatively impact your credit score. So it’s an excellent idea to make sure you trust the primary applicant or have a way to monitor that payments are, in fact, being made so that you don’t end up in a bad financial situation.

 

You’re on the mortgage until they can qualify to remove you.


Once the initial mortgage term has been completed, you won’t be automatically removed from the mortgage. The primary applicant will have to make a new application in their own name and qualify for the mortgage on their own merit. If they don’t qualify, you’ll be kept on the mortgage for the next term.


So before co-signing, it’s a good idea to discuss how long you can expect your name will be on the mortgage. Having a clear and open conversation with the primary applicant and your independent mortgage professional will help outline expectations.


Co-signing a mortgage impacts your debt service ratio.


When you co-sign for a mortgage, all of the debt of the co-signed mortgage is counted in your debt service ratios. This means that if you’re looking to qualify for another mortgage in the future, you’ll have to include the payments of the co-signed mortgage in those calculations, even though you aren’t the one making the payments directly.


As this could significantly impact the amount you could borrow in the future, before you co-sign a mortgage, you’ll want to assess your financial future and decide if co-signing makes sense.


Co-signing a mortgage means helping someone get ahead.


While there are certainly things to consider when agreeing to co-sign on a mortgage application, chances are, by being a co-signor, you'll be helping someone you care for get ahead in life. The key to co-signing well is to outline expectations and over-communicate through the mortgage process.


If you have any questions about co-signing on a mortgage or about the mortgage application process in general, please connect anytime. It would be a pleasure to work with you.


Tim Lyon

Mortgage Consultant

By Tim Lyon October 28, 2025
If you're buying a home with less than 20% down, you'll need something called an insured mortgage. Many borrowers find this confusing at first, especially since it doesn’t refer to insurance for you, the borrower. That’s why I have put together this straightforward breakdown so you understand what insured mortgages are, why they exist, and how they affect your purchase. What Is an Insured Mortgage? A mortgage must be insured when a borrower makes a down payment of less than 20% on a home purchase. The insurance protects the lender (not the borrower) in case the borrower defaults. The insurance is guaranteed by the federal government. So, why do we have this program? It allows borrowers to buy homes with smaller down payments and higher loan-to-value (LTV) ratios. Higher loan-to-value mortgages are inherently more risky because there is not much cushion if the housing market starts to decline. For example, if someone buys a $500,000 home with only 5% down ($25,000), they’ll need a $475,000 mortgage—this is a 95% LTV . If the market drops and the home’s value falls to $470,000, the mortgage would still be $475,000. If the borrower stopped making payments, the lender could lose money after selling the home and paying costs. That kind of loss, multiplied across thousands of borrowers, could threaten the stability of the entire banking system (as we saw in the U.S. in 2008). The mortgage insurance system is designed to prevent that scenario by spreading risk and keeping lenders protected. How Does the Insurance Work? You, the borrower, pay the insurance premium. It's typically added directly to your mortgage balance rather than paid upfront. The cost depends on your down payment size and amortization. Example: Purchase price: $500,000 Down payment: $25,000 (5%) Mortgage amount: $475,000 Insurance premium: 4.2% = $19,950 Total new mortgage: $494,950 The insurance does add cost, but insured mortgages usually offer slightly lower interest rates because the lender's risk is minimal. The rate savings don't fully offset the premium, but they help. The Insurer’s Role For insured mortgages, the insurer’s approval is the most important part of the process. If the insurer won’t approve the file, no lender can. Once the insurer signs off, we can typically find a lender to fund the loan. Canada has three mortgage insurers: CMHC (public) Sagen (private) Canada Guaranty (private) All of the insurers are backed by government guarantees and have to follow similar rules, but each has a few unique programs. Lenders usually choose the insurer, though I sometimes work with them to send a file to a specific insurer if it benefits the borrower. Qualification Rules Because insured mortgages are government-backed, the rules are strict: Debt ratios: 39% of your income can go toward your stress-tested mortgage payment, property taxes, heat, and half of condo fees 44% of your income can go toward the above plus your other debts Down payment: 5% on the first $500,000, 10% on the remainder Maximum purchase price: $1.5 million Amortization: Maximum of 25 years for most buyers; up to 30 years for first-time buyers who qualify under the new federal program Unlike with an uninsured mortgage, where lenders may have some flexibility if your income ratios are slightly above the limits, there is no discretion on an insured mortgage. If your ratios exceed the limits even a little bit, the insurer will decline the application. The Approval Process The process is similar to an uninsured mortgage, with one extra step: We submit your mortgage application to the lender of choice They do their initial review If that looks good, they package it up and send it to the insurer Once the insurer has reviewed and approved it, the file comes back to the lender for final review and approval Common Misunderstandings About Insured Mortgages Many borrowers are surprised to learn the following facts about insured mortgages: You do not need to be a first-time homebuyer to buy with less than 20% down You cannot buy an investment property with less than 20% down You can buy a second home with less than 20% down You cannot refinance an insured mortgage and keep the insurance. If you have an insured mortgage and do refinance, you will lose the insurance. This mostly affects the lender, but it also moves you to uninsured rates. Why Choose an Insured Mortgage? Given the cost and restrictions, why would anyone choose an insured mortgage? The main reason is accessibility . It allows you to buy a home without saving a full 20% down payment, which is increasingly difficult with high home prices and living costs. It can also be a strategic choice. Some buyers prefer to keep more of their savings invested or diversified instead of tying everything up in a down payment. If your investments are earning more than your mortgage costs, keeping that money invested might make financial sense. Real-World Example Let's say you're buying a $600,000 home. Here's how the costs compare between the minimum down payment for an insured mortgage and the minimum down payment for an uninsured mortgage:
By Tim Lyon October 20, 2025
The part of mortgage approval nobody likes but everyone needs