GDS/TDS Ratios Explained

Erik Sepper • March 13, 2024

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.


ERIK SEPPER 
MORTGAGE AGENT

CONTACT ME

Mortgages Aren’t One-Size-Fits-All

By Erik Sepper • September 3, 2025
Why the Cheapest Mortgage Isn’t Always the Smartest Move Some things are fine to buy on the cheap. Generic cereal? Sure. Basic airline seat? No problem. A car with roll-down windows? If it gets you where you're going, great. But when it comes to choosing a mortgage? That’s not the time to cut corners. A “no-frills” mortgage might sound appealing with its rock-bottom interest rate, but what’s stripped away to get you that rate can end up costing you far more in the long run. These mortgages often come with severe limitations—restrictions that could hit your wallet hard if life throws you a curveball. Let’s break it down. A typical no-frills mortgage might offer a slightly lower interest rate—maybe 0.10% to 0.20% less. That could save you a few hundred dollars over a few years. But that small upfront saving comes at the cost of flexibility: Breaking your mortgage early? Expect a massive penalty. Want to make extra payments? Often not allowed—or severely restricted. Need to move and take your mortgage with you? Not likely. Thinking about refinancing? Good luck doing that without a financial hit. Most people don’t plan on breaking their mortgage early—but roughly two-thirds of Canadians do, often due to job changes, separations, relocations, or expanding families. That’s why flexibility matters. So why do lenders even offer no-frills mortgages? Because they know the stats. And they know many borrowers chase the lowest rate without asking what’s behind it. Some banks count on that. Their job is to maximize profits. Ours? To help you make an informed, strategic choice. As independent mortgage professionals, we work for you—not a single lender. That means we can compare multiple products from various financial institutions to find the one that actually suits your goals and protects your long-term financial health. Bottom line: Don’t let a shiny low rate distract you from what really matters. A mortgage should fit your life—not the other way around. Have questions? Want to look at your options? I’d be happy to help. Let’s chat.

From Summer Shine to Fall Fine: Smart Home Projects to Tackle Before the First Frost

By Erik Sepper • August 28, 2025
As patios wind down and pumpkin spice ramps up, fall is the perfect reset for your home—and your homeowner game plan. These quick wins boost comfort, curb appeal, and efficiency now, and set you up for a low-stress winter (and a strong spring market). 1) Safety & “silent leak” checks (Weekend-ready) Clean gutters & downspouts. Add leaf guards where trees overhang. Roof scan. Look for lifted shingles, cracked flashings, or moss. Seal the shell. Re-caulk window/door trim; replace weatherstripping. Test alarms. New batteries for smoke/CO detectors; add one near bedrooms. Why it matters: Prevent water intrusion and heat loss before storms roll in. 2) Heat smarter, not harder Furnace/boiler tune-up and filter change. Smart thermostat with schedules and geofencing. Draft hunt. Foam gaskets behind outlets, door sweeps on exterior doors. ROI tip: Efficiency upgrades lower monthly bills and can improve lender ratios if you’re eyeing a refinance later. 3) Fall-proof your yard (so spring you says “thanks”) Aerate + overseed + fall fertilize for thicker turf next year. Trim trees/shrubs away from siding and power lines. Mulch perennials and plant spring bulbs now. Shut off/bleed exterior taps and store hoses to avoid burst pipes. 4) Extend outdoor season (cozy edition) Portable fire pit or propane heater + layered blankets. Path/step lighting for darker evenings (solar or low-voltage). Weather-resistant storage for cushions/tools to preserve value. Neighborhood curb appeal: Warm lighting and tidy beds make a big first impression if you list in shoulder season. 5) Water management = winter peace of mind Re-grade low spots and add downspout extensions (2–3+ metres). Check sump pump (and backup). Look for efflorescence or damp corners in the basement. 6) Mini-renos that punch above their weight Entry/mudroom upgrade: hooks, bench, boot trays, closed storage. Laundry room tune-up: counter over machines, sorting bins, task lighting. Kitchen refresh: new hardware, tap, and under-cabinet lighting in one afternoon. Budget guide: Many of these land under a micro-reno budget—perfect for a modest line of credit. 7) Indoor air quality tune-up Deep clean vents and dryers (including the rigid duct). Add door mats (exterior + interior) to catch grit/salt. Houseplants or HEPA purifier for closed-window months. Fast Timeline (pin this to the fridge) Late August–September Gutters/downspouts, roof/caulking, HVAC service, lawn care, plant bulbs, exterior tap shut-off plan, path lighting. October Weatherstripping/sweeps, fire pit setup, organize mudroom/garage, test alarms, sump check, downspout extensions, dryer vent cleaning. Financing smarter: make your mortgage work for your home Annual mortgage check-in. As rates, income, and goals evolve, a quick review can free up cash flow or open options for a small fall project budget. HELOC vs. top-up refinance. For bite-size projects, a HELOC can be flexible. For bigger renos you plan to pay down, a top-up refi might make more sense. Bundle & prioritize. Knock out the high-impact, low-cost items first (air sealing, safety, water management) before the cosmetic upgrades. Not sure which route fits your fall plans? We’ll run the numbers and map the best financing path for your specific budget and goals. Quick Checklist (copy/paste) ☐ Clean gutters/downspouts; add guards ☐ Roof & flashing visual check ☐ Re-caulk, weatherstrip, add door sweeps ☐ HVAC service + new filter ☐ Aerate/overseed/fertilize; trim trees; plant bulbs ☐ Path & entry lighting ☐ Drain/bleed outdoor taps; store hoses ☐ Downspout extensions; sump test ☐ Dryer vent cleaning ☐ Mudroom/garage organization ☐ Schedule mortgage review / discuss HELOC vs refi Ready to make fall your low-stress season? Book a quick fall mortgage check-up—15 minutes to see if a small credit line or a tweak to your current mortgage could cover your priority projects without straining cash flow.

Everything You Should Know Before Buying a Home

By Erik Sepper • August 27, 2025
Thinking About Buying a Home? Here’s What to Know Before You Start Whether you're buying your very first home or preparing for your next move, the process can feel overwhelming—especially with so many unknowns. But it doesn’t have to be. With the right guidance and preparation, you can approach your home purchase with clarity and confidence. This article will walk you through a high-level overview of what lenders look for and what you’ll need to consider in the early stages of buying a home. Once you’re ready to move forward with a pre-approval, we’ll dive into the details together. 1. Are You Credit-Ready? One of the first things a lender will evaluate is your credit history. Your credit profile helps determine your risk level—and whether you're likely to repay your mortgage as agreed. To be considered “established,” you’ll need: At least two active credit accounts (like credit cards, loans, or lines of credit) Each with a minimum limit of $2,500 Reporting for at least two years Just as important: your repayment history. Make all your payments on time, every time. A missed payment won’t usually impact your credit unless you’re 30 days or more past due—but even one slip can lower your score. 2. Is Your Income Reliable? Lenders are trusting you with hundreds of thousands of dollars, so they want to be confident that your income is stable enough to support regular mortgage payments. Salaried employees in permanent positions generally have the easiest time qualifying. If you’re self-employed, or your income includes commission, overtime, or bonuses, expect to provide at least two years’ worth of income documentation. The more predictable your income, the easier it is to qualify. 3. What’s Your Down Payment Plan? Every mortgage requires some amount of money upfront. In Canada, the minimum down payment is: 5% on the first $500,000 of the purchase price 10% on the portion above $500,000 20% for homes over $1 million You’ll also need to show proof of at least 1.5% of the purchase price for closing costs (think legal fees, appraisals, and taxes). The best source of a down payment is your own savings, supported by a 90-day history in your bank account. But gifted funds from immediate family and proceeds from a property sale are also acceptable. 4. How Much Can You Actually Afford? There’s a big difference between what you feel you can afford and what you can prove you can afford. Lenders base your approval on verifiable documentation—not assumptions. Your approval amount depends on a variety of factors, including: Income and employment history Existing debts Credit score Down payment amount Property taxes and heating costs for the home All of these factors are used to calculate your debt service ratios—a key indicator of whether your mortgage is affordable. Start Early, Plan Smart Even if you’re months (or more) away from buying, the best time to start planning is now. When you work with an independent mortgage professional, you get access to expert advice at no cost to you. We can: Review your credit profile Help you understand how lenders view your income Guide your down payment planning Determine how much you can qualify to borrow Build a roadmap if your finances need some fine-tuning If you're ready to start mapping out your home buying plan or want to know where you stand today, let’s talk. It would be a pleasure to help you get mortgage-ready.