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For informational purposes only. Not financial, legal, or professional advice. Consult a licensed mortgage professional before making decisions. See full disclaimer

FAQ Library
Regulatory•Verified 2026-02-18

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.

Key Points

  • 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.

Need a Deeper Breakdown?

Read the full research guide this FAQ was derived from for more context and strategy.

Technical Research Verification

Our systems synchronized 3 data points and regulatory frameworks to verify this technical brief.

Read the deeper guide · Regulatory

GDS & TDS Ratios Explained: 2026 Canadian Mortgage Qualification Guide

Related Questions

How does the new OSFI guidance affect mortgage switching for you?

The latest OSFI guidance simplifies switching lenders at renewal for borrowers with existing uninsured mortgages.

What documentation is typically required for a mortgage application, and how might this differ for a 'straight switch'?

While specific requirements can vary slightly among lenders, the standard documentation confirms income, credit history, and property details.

What are the Loan-to-Income (LTI) limits, and how do they impact lenders?

OSFI is introducing Loan-to-Income (LTI) limits on the uninsured mortgage portfolios of federally regulated financial institutions (FRFIs).

How does 'stress testing' affect the stability of financial institutions?

Stress testing evaluates how a financial institution's mortgage portfolio would fare under tough economic times.

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