Mortgage Approval 101: GDS & TDS Explained

Rabinder Dhillon • September 3, 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.


RABINDER
MORTGAGE BROKER

LET'S CONNECT

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

By Rabinder Dhillon • August 27, 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.

Options For Your Downpayment

By Rabinder Dhillon • August 27, 2025
Your downpayment refers to the initial payment you make when buying a property through mortgage financing. A downpayment is always required when purchasing, because in Canada, lenders are only allowed to lend up to 95% of the property value, leaving you with the need to come up with at least 5% for a downpayment. In fact, securing mortgage financing with anything less than 20% down is only made possible through mortgage default insurance. Canada has three default insurance providers: the Canadian Mortgage and Housing Corporation (CMHC), Sagen (formerly Genworth Canada), and Canada Guaranty. There is a cost for default insurance which is usually rolled into the total mortgage amount and is tiered depending on how much you put down. As your downpayment can be a significant amount of money, you probably need a plan to put this money together. So, let’s take a look at some of the options you have to come up with a downpayment. Money from your resources If you’ve been saving money and have accumulated the funds and set them aside for to use for your downpayment, you'll need to prove a 90-day history of those funds. As far as the lender is concerned, this is the most straightforward way to prove a downpayment. Any large deposits to your bank account that aren’t from payroll will require you to prove the source of funds. For example, if you recently sold a vehicle, you’ll need to provide the paperwork as proof of ownership, which corresponds to your account’s deposit. Or, if you have funds in an investment account that you’ve transferred over, statements of that transfer or account would suffice. You have to prove the source of your downpayment funds to the lender when qualifying for a mortgage to help prevent money laundering. Funds from the sale of another property If you’ve recently sold a property and you’re using the proceeds of that sale as the downpayment from your new purchase, you can provide the paperwork from that transaction to substantiate your downpayment. RRSPs through the Home Buyer’s Plan Okay, so let’s say you don’t have all the money set aside in your savings, but you do have cash in your RRSP. Assuming you’re a first-time homebuyer, you can access the funds from your RRSP Tax-Free to use as a downpayment. You’re able to access up to $35k individually or $70k as a couple. The money has to be paid back over the next 15 years. If you’d like more information on what this program looks like, please get in touch. Gifted downpayment Now, if you don’t have enough money in your savings, but you have a family member who is willing to help, they can gift you funds for your downpayment. With the increased cost of living, making it harder to save for a downpayment, receiving a gift from a family member is becoming increasingly commonplace. Now, to qualify, the gift has to come from an immediate family member who will sign a gift letter indicating there is no schedule of repayment and that the gift doesn’t have to be repaid. Proof that the money has been deposited into your account is required through bank statements. Gifted funds can make up part of or the entire amount of downpayment. For example, if you purchase a property for $300k and have $10k saved up, your parents can gift you the remaining $5k to make up the total 5% downpayment. Borrowed downpayment Suppose you aren’t fortunate enough to have a family member who can gift you a downpayment, but you have excellent credit and a high income compared to the amount you’re looking to borrow. In that case, you might qualify to borrow part or all of your downpayment. It’s possible to borrow your downpayment as long as you include the payments in your debt service ratios. Typically this is 3% of the outstanding balance. So there you have it, to qualify for a mortgage, you’ll need to come up with a downpayment. That can be through your resources, a property you sold, an RRSP, a gift from a family member, borrowed funds, or a combination of all five sources. If you’d like to discuss your downpayment or anything else related to mortgage financing; it’s never too early to start the conversation about getting pre-approved for a mortgage. Please connect anytime. It would be a pleasure to work with you!