GDS/TDS Ratios Explained

Karen McKenzie • November 15, 2023

One of the major qualifiers lenders look at when considering your application for mortgage financing is your debt service ratios.


Now, before we get started, if you prefer to have someone walk through these calculations with you, assess your financial situation, and let you know exactly where you stand, let’s connect. There is no use in dusting off the calculator and running the numbers yourself when we can do it for you!


However, if you’re someone who likes to know the nitty-gritty of how things work instead of simply accepting that's just the way it is, this article is for you. But be warned, there are a lot of mortgage words and some math ahead; with that out of the way, let’s get started!

 

“Debt servicing” is the measure of your ability to meet all of your financial obligations. There are two ratios that lenders examine to determine whether you can debt service a mortgage.


The first is called the “gross debt service” ratio, or GDS, which is the percentage of your monthly household income that covers your housing costs. The second is called the “total debt service” ratio, or TDS, which is the percentage of your monthly household income covering your housing costs and all your other debts.


GDS is your income compared to the cost of financing the mortgage, including your proposed mortgage payments (principal and interest), property taxes, and heat (PITH), plus a percentage of your condo fees (if applicable).


Here’s how to calculate your GDS.


Principal + Interest + Taxes + Heat / Gross Annual Income


Your TDS is your income compared to your GDS plus the payments made to service any existing debts. Debts include car loans, line of credit, credit card payments, support payments, student loans, and anywhere else you’re contractually obligated to make payments.


Here’s how to calculate your TDS.


Principal + Interest + Taxes + Heat + Other Debts / Gross Annual Income


With the calculations for those ratios in place, the next step is to understand that each lender has guidelines that outline a maximum GDS/TDS. Exceeding these guidelines will result in your mortgage application being declined, so the lower your GDS/TDS, the better.


If you don’t have any outstanding debts, your GDS and TDS will be the same number. This is a good thing!


The maximum ratios vary for conventional mortgage financing based on the lender and mortgage product being offered. However, if your mortgage is high ratio and mortgage default insurance is required, the maximum GDS is 39% with a maximum TDS of 44%.


So how does this play out in real life? Well, let’s say you’re currently looking to purchase a property with a payment of $1700/mth (PITH), and your total annual household income is $90,000 ($7500/mth). The calculations would be $1700 divided by $7500, which equals 0.227, giving you a gross debt service ratio of 22.7%.


A point of clarity here. When calculating the principal and interest portion of the payment, the Government of Canada has instituted a stress test. It requires you to qualify using the government's qualifying rate (which is higher), not the actual contract rate. This is true for both fixed and variable rate mortgages.


Now let’s continue with the scenario. Let’s say that in addition to the payments required to service the property, you have a car payment of $300/mth, child support payments of $500/mth, and between your credit cards and line of credit, you’re responsible for another $700/mth. In total, you pay $1500/mth. So when you add in the $1700/mth PITH, you arrive at a total of $3200/mth for all of your financial obligations. $3200 divided by $7500 equals 0.427, giving you a total debt service ratio of 42.7%.


Here’s where it gets interesting. Based on your GDS alone, you can easily afford the property. But when you factor in all your other expenses, the TDS exceeds the allowable limit of 42% (for an insured mortgage anyway). So why does this matter? Well, as it stands, you wouldn’t qualify for the mortgage, even though you are likely paying more than $1700/mth in rent.


So then, to qualify, it might be as simple as shuffling some of your debt to lower payments. Or maybe you have 10% of the purchase price saved for a downpayment, changing the mortgage structure to 5% down and using the additional 5% to pay out a portion of your debt might be the difference you need to bring it all together.


Here’s the thing, as your actual financial situation is most likely different than the one above, working with an independent mortgage professional is the best way to give yourself options. Don’t do this alone. Your best plan is to seek and rely on the advice provided by an experienced independent mortgage professional. While you might secure a handful of mortgages over your lifetime, we do this every day with people just like you.


It’s never too early to start the conversation about mortgage qualification. Going over your application and assessing your debt service ratios in detail beforehand gives you the time needed to make the financial moves necessary to put yourself in the best financial position.


So if you find yourself questioning what you can afford or if you want to discuss your GDS/TDS ratios to understand the mortgage process a little better, please get in touch. It would be a pleasure to work with you, we can get a preapproval started right away.

Karen McKenzie

Canadian Mortgage Expert

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What is a Cashback Mortgage?

By Karen McKenzie • March 26, 2025
As the name implies, a cashback mortgage is similar to a standard mortgage, except that you receive a lump sum of cash upon closing. This lump sum will either be a fixed amount of money or a percentage of the mortgage amount, usually between 1-7%, depending on the mortgage term selected. How you use the cash is entirely up to you. Some of the most common reasons to secure a cashback mortgage are to: Cover closing costs. Buy new furniture. Renovate your property. Supplement cashflow. Consolidate higher-interest debt. Really, you can use the cash for anything you like. It’s tax-free and paid to you directly once the mortgage closes. Understanding the cost of a cashback mortgage. Now, while it might appear like a cashback mortgage is a great way to get some free money, it’s not. Banks aren’t altruistic; they’re in the business of making money by lending money. Securing a mortgage that provides you with cash back at closing will cost you a higher interest rate over your mortgage term. A cashback mortgage is like getting a fixed loan rolled into your mortgage. Your interest rate is increased to cover the additional funds being lent. Now, with so many different cashback options available and with interest rates constantly changing, it's nearly impossible to run through specific calculations on a simple article to outline how much more you’d pay over the term. So, if you'd like to identify the true cost of securing a cashback mortgage, the best place to start is to discuss your financial situation with an independent mortgage professional. When you work with an independent mortgage professional instead of a single bank, you receive unbiased advice, more financing options, and a clear picture of the cost associated with securing a mortgage. Getting cashback at closing is a mortgage feature that makes the bank more money at your expense. This isn’t necessarily a bad thing; the key is to be informed of the costs involved so you can make a good decision. Eligibility for a cashback mortgage. Simply put, a cashback mortgage isn’t for everyone. This is a mortgage product that has tougher qualifications than standard mortgage financing. Any lender willing to offer a cashback mortgage will want to see that you have stable employment, a fabulous credit score, and healthy debt service ratios. If your mortgage application is in any way “unique,” the chances of qualifying for a cashback mortgage are pretty slim. Breaking your mortgage term early. In addition to paying a higher interest rate to cover the cost of receiving the cashback at closing, a cashback mortgage also limits your options down the line. If your life circumstances change and you need to break your mortgage mid-term, depending on the conditions set out in your mortgage contract, you’ll most likely be required to either pay all of the cashback received or at least a portion, depending on how long you’ve had the mortgage. As all cashback mortgages are tied to fixed-rate terms, so in addition to repaying the cashback, you’d also be required to pay the interest rate differential penalty; or 3 months interest, whichever is greater for breaking your mortgage term early. Sufficed to say, should you need to pay out your mortgage early, breaking your cashback mortgage will be costly. Certainly, this is something to consider when assessing the suitability of this mortgage product. Get independent mortgage advice. Understanding the intricacies of mortgage financing can be difficult at the best of times. With all the different terms, rates, and mortgage products available, it’s hard to know which mortgage is best for you. So while a mortgage that offers a cash incentive upon closing might initially seem like an attractive offer, make sure you seek out the guidance of an independent mortgage professional to help you navigate the costs associated with a cashback mortgage. While it might be a great option for you, there might be other mortgage options that better suit your needs. It's worth a conversation for sure! If you’d like to discuss what a cashback mortgage or any other mortgage product would look like for you, please get in touch. It would be a pleasure to work with you.

Buying a Second Property

By Karen McKenzie • March 19, 2025
If you’ve been thinking about buying a second property and you’re looking to put some of the pieces together, you’ve come to the right place! Whether you’re looking to buy a vacation property, start a rental portfolio, or help accommodate a family member, there are many reasons to buy a second property (while keeping your existing property), which might make sense for you! Now, while there are many great reasons to buy a second property, there is also a lot to know as you walk through the process. The key here is to have absolute clarity around your why. Ask yourself, why do you want to buy a second property? This isn’t a decision to be taken lightly or one that should be made too quickly. Buying a second property should be a strategic decision that allows you to accomplish your goals, and it should include an assessment of your overall financial health. So with clear goals in mind, the best place to start the process is to have a conversation with an independent mortgage professional. This will allow you to assess your financial situation, outline the costs, and put together a plan to make it happen. While purchasing a second property is similar to buying a primary residence, there are some key differences. Just because you’ve qualified in the past for your existing mortgage doesn’t mean you’ll qualify to purchase a second property. One key difference is the amount of downpayment you might be required to come up with. A property that is owner-occupied or occupied by a family member on a rent-free basis will require less of a downpayment than if the second property will be used to generate an income. So, depending on the property's intended use, you might have to come up with as much as 25%-35% down. This is where strategic planning comes in. Consider unlocking the equity in your existing home to finance the downpayment to purchase your second home. Here are a few ways you can go about doing that: Securing a new mortgage if you own your property clear title Refinancing your existing mortgage to access additional funds Securing a home equity line of credit (HELOC) Getting a second mortgage behind your existing first mortgage Securing a reverse mortgage The conversation about buying a second property should include assessing your overall financial health, leveraging your existing assets to lower your overall cost of borrowing, and figuring out the best way to accomplish your goals. And as it's impossible to outline every scenario in a simple blog post, if you’d like to discuss your goals and put a plan together to finance a second property, connect anytime. It would be a pleasure to work with you.
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