Mortgage Approval 101: GDS & TDS Explained

Tim Lacroix • August 20, 2025

Can You Afford That Mortgage? Let’s Talk About Debt Service Ratios

One of the biggest factors lenders look at when deciding whether you qualify for a mortgage is something called your debt service ratios. It’s a financial check-up to make sure you can handle the payments—not just for your new home, but for everything else you owe as well.


If you’d rather skip the math and have someone walk through this with you, that’s what I’m here for. But if you like to understand how things work behind the scenes, keep reading. We’re going to break down what these ratios are, how to calculate them, and why they matter when it comes to getting approved.


What Are Debt Service Ratios?

Debt service ratios measure your ability to manage your financial obligations based on your income. There are two key ratios lenders care about:

  1. Gross Debt Service (GDS)
    This looks at the percentage of your income that would go toward housing expenses only.

  2. Total Debt Service (TDS)
     This includes your housing costs plus all other debt payments—car loans, credit cards, student loans, support         payments, etc.


How to Calculate GDS and TDS

Let’s break down the formulas.


GDS Formula:

(P + I + T + H + Condo Fees*) ÷ Gross Monthly Income


Where:

P = Principal

I = Interest

T = Property Taxes

H = Heat


Condo fees are usually calculated at 50% of the total amount


TDS Formula:

(GDS + Monthly Debt Payments) ÷ Gross Monthly Income


These ratios tell lenders if your budget is already stretched too thin—or if you’ve got room to safely take on a mortgage.


How High Is Too High?


Most lenders follow maximum thresholds, especially for insured (high-ratio) mortgages.

As of now, those limits are typically:

GDS: Max 39%

TDS: Max 44%


Go above those numbers and your application could be declined, regardless of how confident you feel about your ability to manage the payments.


Real-World Example

Let’s say you’re earning $90,000 a year, or $7,500 a month.

You find a home you love, and the monthly housing costs (mortgage payment, property tax, heat) total $1,700/month.


GDS = $1,700 ÷ $7,500 = 22.7%


You’re well under the 39% cap—so far, so good.


Now factor in your other monthly obligations:

  • Car loan: $300
  • Child support: $500
  • Credit card/line of credit payments: $700
    Total other debt = $1,500/month


Now add that to the $1,700 in housing costs:
TDS = $3,200 ÷ $7,500 = 42.7%


Uh oh. Even though your GDS looks great, your TDS is just over the 42% limit. That could put your mortgage approval at risk—even if you’re paying similar or higher rent now.


What Can You Do?

In cases like this, small adjustments can make a big difference:

  • Consolidate or restructure your debts to lower monthly payments
  • Reallocate part of your down payment to reduce high-interest debt
  • Add a co-applicant to increase qualifying income
  • Wait and build savings or credit strength before applying


This is where working with an experienced mortgage professional pays off. We can look at your entire financial picture and help you make strategic moves to qualify confidently.


Don’t Leave It to Chance

Everyone’s situation is different, and debt service ratios aren’t something you want to guess at. The earlier you start the conversation, the more time you’ll have to improve your numbers and boost your chances of approval.


If you're wondering how much home you can afford—or want help analyzing your own GDS and TDS—let’s connect. I’d be happy to walk through your numbers and help you build a solid mortgage strategy.


Tim Lacroix

Mortgage Broker

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Costs Associated with Buying Property

By Tim Lacroix • November 19, 2025
When calculating if you can afford to purchase a property, don’t just figure out a rough downpayment and quickly move on from there. Several other costs need to be considered when buying a property; these are called your closing costs. Closing costs refer to the things you’ll have to pay for out of your pocket and the amount of money necessary to finalize the purchase of a property. And like most things in life, it pays to plan ahead when it comes to closing costs. Closing costs should be part of the pre-approval conversation as they are just as important as saving for your downpayment. Now, if your mortgage is high-ratio and requires mortgage default insurance, the lender will need to confirm that you have at least 1.5% of the purchase price available to close the mortgage. This is in addition to your downpayment. So if your downpayment is 10% of the purchase price, you’ll want to have at least 11.5% available to bring everything together. But of course, the more cash you have to fall back on, the better. So with that said, here is a list of the things that will cost you money when you’re buying a property. As prices vary per service, if you’d like a more accurate estimate of costs, please connect anytime, it would be a pleasure to walk through the exact numbers with you. Inspection or Appraisal A home inspection is when you hire a professional to assess the property's condition to make sure that you won’t be surprised by unexpected issues. An appraisal is when you hire a professional to compare the property's value against other properties that have recently sold in the area. The cost of a home inspection is yours, while the appraisal cost is sometimes covered by your mortgage default insurance and sometimes covered by you! Lawyer or Notary Fees To handle all the legal paperwork, you’re required to hire a legal real estate professional. They’ll be responsible for transferring the title from the seller's name into your name and make sure the lender is registered correctly on the title. Chances are, this will be one of your most significant expenses, except if you live in a province with a property transfer tax. Taxes Depending on which province you live in and the purchase price of the property you’re buying, you might have to pay a property transfer tax or land transfer tax. This cost can be high, upwards of 1-2% of the purchase price. So you’ll want to know the numbers well ahead of time. Insurance Before you can close on mortgage financing, all financial institutions want to see that you have property/home insurance in place for when you take possession. If disaster strikes and something happens to the property, your lender must be listed on your insurance policy. Unlike property insurance, which is mandatory, you might also consider mortgage insurance, life insurance, or a disability insurance policy that protects you in case of unforeseen events. Not necessary, but worth a conversation. Moving Expenses Congratulations, you just bought a new property; now you have to get all your stuff there! Don’t underestimate the cost of moving. If you’re moving across the country, the cost of hiring a moving company is steep, while renting a moving truck is a little more reasonable; it all adds up. Hopefully, if you’re moving locally, your costs amount to gas money and pizza for friends. Utilities Hooking up new services to a property is more time-consuming than costly. However, if you’re moving to a new province or don’t have a history of paying utilities, you might be required to come up with a deposit for services. It doesn’t really make sense to buy a property if you can’t afford to turn on the power or connect the water. So there you have it; this covers most of the costs associated with buying a new property. However, this list is by no means exhaustive, but as mentioned earlier, planning for these costs is a good idea and should be part of the pre-approval process. If you have any questions about your closing costs or anything else mortgage-related, please connect anytime; it would be great to hear from you!

How to Raise Your Credit Score and Unlock Better Rates

By Tim Lacroix • November 12, 2025
Want a Better Credit Score? Here’s What Actually Works Your credit score plays a major role in your ability to qualify for a mortgage—and it directly affects the interest rates and products you’ll be offered. If your goal is to access the best mortgage options on the market, improving your credit is one of the smartest financial moves you can make. Here’s a breakdown of what truly matters—and what you can start doing today to build and maintain a strong credit profile. 1. Always Pay On Time Late payments are the fastest way to damage your credit score—and on-time payments are the most powerful way to boost it. When you borrow money, whether it’s a credit card, car loan, or mortgage, you agree to repay it on a schedule. If you stick to that agreement, lenders reward you with good credit. But if you fall behind, missed payments are reported to credit bureaus and your score takes a hit. A single missed payment over 30 days late can hurt your score. Missed payments beyond 120 days may go to collections—and collections stay on your report for up to six years . Quick tip: Lenders typically report missed payments only if they’re more than 30 days overdue. So if you miss a Friday payment and make it up on Monday, you're probably in the clear—but don't make it a habit. 2. Avoid Taking On Unnecessary Credit Once you have at least two active credit accounts (like a credit card and a car loan), it’s best to pause on applying for more—unless you truly need it. Every time a lender checks your credit, a “hard inquiry” appears on your report. Too many inquiries in a short time can bring your score down slightly. Better idea? If your current lender offers a credit limit increase , take it. Higher available credit (when used responsibly) actually improves your credit utilization ratio, which we’ll get into next. 3. Keep Credit Usage Low How much of your available credit you actually use—also known as credit utilization —is another major factor in your score. Here’s the sweet spot: Aim to use 15–25% of your limit if possible. Never exceed 60% , especially if you plan to apply for a mortgage soon. So, if your credit card limit is $5,000, try to keep your balance under $1,250—and pay it off in full each month. Maxing out your cards or carrying high balances (even if you make the minimum payment) can tank your score. 4. Monitor Your Credit Report About 1 in 5 credit reports contain errors. That’s not a small number—and even a minor mistake could cost you when it’s time to get approved for a mortgage. Check your report at least once a year (or sign up for a monitoring service). Look for: Incorrect balances Accounts you don’t recognize Missed payments you know were paid You can request reports directly from Equifax and TransUnion , Canada’s two national credit bureaus. If something looks off, dispute it right away. 5. Deal with Collections Fast If you spot an account in collections—don’t ignore it. Even small unpaid bills (a leftover phone bill, a missed utility payment) can drag down your score for years. Reach out to the creditor or collection agency and arrange payment as quickly as possible . Once settled, ask for written confirmation and ensure it’s updated on your credit report. 6. Use Your Credit—Don’t Just Hold It Credit cards won’t help your score if you’re not using them. Inactive cards may not report consistently to the credit bureaus—or worse, may be closed due to inactivity. Use your cards at least once every three months. Many people put routine expenses like groceries or gas on their cards and pay them off right away. It’s a simple way to show regular, responsible use. In Summary: Improving your credit score isn’t complicated, but it does take consistency: Pay everything on time Keep balances low Limit new credit applications Monitor your report and handle issues quickly Use your credit regularly Following these principles will steadily increase your creditworthiness—and bring you closer to qualifying for the best mortgage rates available. Ready to review your credit in more detail or start prepping for a mortgage? I’m here to help—reach out anytime!