# GDS & TDS Ratios Explained: 2026 Canadian Mortgage Qualification Guide > Understand how Gross Debt Service (GDS) and Total Debt Service (TDS) ratios determine your mortgage eligibility in Canada. This guide covers 2026 qualification rules, the federal stress test (Minimum Qualifying Rate), insured vs. uninsured thresholds, 30-year amortization eligibility, and practical strategies to improve your ratios before applying. Category: Regulatory Last verified: 2026-02-18 Source: https://ratellow.com/guides/gds-tds-qualifying-ratios ## TL;DR - GDS (Gross Debt Service) measures housing costs as a percentage of gross income; TDS (Total Debt Service) adds all other debt payments to that calculation. - For insured mortgages (under 20% down), the maximum GDS is 39% and the maximum TDS is 44% — these are hard federal limits. - For uninsured mortgages, lenders typically apply the same 39%/44% thresholds, though some have stricter internal overlays based on risk profile. - All new mortgage applications in 2026 must pass the federal stress test using the Minimum Qualifying Rate (MQR): the greater of 5.25% or your contract rate plus 2%. - Uninsured borrowers switching lenders at renewal are exempt from the stress test in 2026, but GDS and TDS ratios still apply at the new lender. - First-time buyers and new build purchasers may qualify for 30-year amortizations, which lower monthly payments and can improve TDS ratios. - Reducing existing debts before applying is one of the most effective ways to lower your TDS ratio and qualify for a larger mortgage. ## GDS & TDS Ratios Explained: 2026 Canadian Mortgage Qualification Guide Understanding GDS (Gross Debt Service) and TDS (Total Debt Service) ratios is essential for Canadian homebuyers and homeowners. These ratios determine how much of your gross income can go toward housing costs and total debt payments, directly impacting your mortgage approval and the amount you can borrow. For insured mortgages (those with less than 20% down payment), lenders must apply a maximum GDS of 39% and TDS of 44%. For uninsured mortgages, lenders may apply the same thresholds, though some use stricter internal limits. In 2026, with elevated interest rates and updated federal rules—including the stress test exemption for uninsured borrowers switching lenders at renewal, and expanded 30-year amortizations for first-time buyers and new builds—knowing your ratios helps you make informed decisions. By paying down existing debts, budgeting accurately for housing costs, and exploring all available mortgage options, you can meaningfully improve your chances of approval and ensure your mortgage remains affordable as market conditions evolve. - GDS and TDS ratios set the limits for how much mortgage you can afford — insured borrowers must stay at or below 39% GDS and 44% TDS. - 2026 rules allow uninsured borrowers switching lenders at renewal to skip the federal stress test, giving you more flexibility to shop for better rates. - First-time buyers and purchasers of new builds may qualify for 30-year amortizations, reducing monthly payments and improving your TDS ratio. - Paying down credit cards, car loans, or lines of credit before applying can lower your TDS ratio and unlock a larger mortgage amount. - The federal stress test (Minimum Qualifying Rate, or MQR) requires lenders to qualify you at the greater of 5.25% or your contract rate plus 2% — even if your actual rate is lower. ## Strategy & FAQ As a mortgage broker, GDS (Gross Debt Service) and TDS (Total Debt Service) ratios are among the most critical variables you'll manage for clients. For insured deals, OSFI and CMHC guidelines cap GDS at 39% and TDS at 44% — but many lenders apply tighter overlays, particularly for borrowers with variable income or non-traditional employment. For uninsured mortgages, some lenders hold to the same 39%/44% thresholds while others flex to 40%/45% depending on credit profile and loan-to-value. In 2026, the stress test exemption for uninsured renewals switching lenders opens new rate-shopping opportunities — but GDS/TDS still apply at the new lender's qualifying rate. Knowing which lenders use gross vs. add-back income for self-employed clients, and which accept rental offset at 50% vs. 80%, can be the difference between an approval and a decline. Use these ratio thresholds as your first filter when structuring a deal. ### What exactly are GDS and TDS ratios, and how are they calculated? Gross Debt Service (GDS) and Total Debt Service (TDS) ratios are vital metrics Federally Regulated Financial Institutions (FRFIs) use to assess a borrower's ability to manage debt. GDS calculates your mortgage payments plus property costs as a percentage of your gross income, while TDS includes all other debts, like credit card payments. - Lenders look closely at your finances and may use a higher interest rate than you'll actually pay, just to be safe. - If you need mortgage insurance, there are limits to how much of your income can go towards housing costs. - Private mortgage insurers also have rules about how much debt you can handle to qualify for their insurance. - Lenders generally want to see that your debt levels are comfortably below their maximum allowed amounts. - Your mortgage payments, property taxes, heating, condo fees, and other debts all affect how much you can borrow. ### How do lenders use GDS and TDS to determine if I qualify for a mortgage? Lenders use GDS and TDS ratios to evaluate your ability to handle debt obligations, with willingness and capacity being primary credit decision factors. FRFIs have established debt serviceability metrics in their Residential Mortgage Underwriting Policy (RMUP) to guide affordability assessments. - Lenders follow rules to make sure you can comfortably afford your mortgage. - If you have mortgage insurance, the insurer sets the rules for how much debt you can handle. - If you don't have mortgage insurance, lenders will look at your current and future finances to decide if you qualify for a mortgage. - To qualify for a mortgage without insurance, you'll need to prove you can afford an interest rate higher than what's offered, or a minimum rate. - The government reviews this higher qualifying interest rate regularly and can change it. ### How can I improve my GDS and TDS ratios to qualify for a larger mortgage? Improving your GDS and TDS ratios involves reducing debt or increasing income, potentially qualifying you for a larger mortgage. Paying down existing debts, like credit cards, will lower your monthly obligations; consider exploring options for increasing your income. - Your GDS and TDS are key to showing lenders you can handle your mortgage payments. - When you renew your mortgage, lenders will look at your finances as if you're a new customer. - Lenders will check if you can still afford your payments if interest rates go up or your income goes down. - You'll generally need a credit score of 600 or higher to get approved for a mortgage. - For mortgages with a small down payment, lenders usually want your GDS to be below 39% and your TDS below 44%. ## Sources - Debt service coverage — https://www.osfi-bsif.gc.ca/en/guidance/guidance-library/residential-mortgage-underwriting-practices-procedures-guideline-2017#2.3.3 - Page 3 — https://assets.cmhc-schl.gc.ca/sf/project/cmhc/pdfs/factsheets/new/cmhc-quick-reference.pdf#page=3 - I. Purpose and scope of the guideline — https://www.osfi-bsif.gc.ca/en/guidance/guidance-library/residential-mortgage-underwriting-practices-procedures-guideline-2017#1.0