5 Numbers Every Canadian Should Know Before Getting a Mortgage (2026)

Before you apply for a mortgage in 2026, there are 5 numbers that quietly decide how much you can borrow, what rate you're offered, and whether you're approved at all. Knowing them in advance lets you fix weak spots before a lender ever sees your file. Estimate your affordability to see where you stand.

The short answer

Lenders judge your application on five core figures. Get them in good shape and your approval gets bigger and cheaper. The 5 numbers every Canadian should know are:

• Your credit score — how reliably you repay debt.
• Your GDS ratio — housing costs as a share of income.
• Your TDS ratio — all debt payments as a share of income.
• Your loan-to-value (LTV) — how much you borrow versus the home's value.
• The stress-test qualifying rate — the higher rate you must qualify at.

1. Your credit score

Your credit score is a three-digit number (roughly 300 to 900) that tells lenders how reliably you repay debt. Most prime lenders look for a score around 680 or higher for the best rates, though approvals are possible lower. Pay on time, keep balances well below limits, and avoid new debt before applying.

A stronger score doesn't just affect approval — it widens the pool of lenders competing for you, which usually means a lower rate. If your score is thin or bruised, an alternative lender can bridge the gap while you rebuild, then you switch to prime at renewal.

2. Your GDS ratio

Gross Debt Service (GDS) is the share of your gross monthly income that goes to housing costs — mortgage principal and interest, property taxes, heat, and half of any condo fees. Lenders generally want GDS at or below about 39%. Lower it by raising income or reducing the mortgage amount.

Because the mortgage portion of GDS is calculated at the stress-test rate rather than your contract rate, your qualifying housing cost is higher than the payment you'll actually make. That's deliberate — it confirms you'd cope if rates rose.

3. Your TDS ratio

Total Debt Service (TDS) is GDS plus every other monthly debt payment — car loans, credit cards (lenders count roughly 3% of the balance), lines of credit, student loans, and support payments. Lenders generally cap TDS at about 44%. Clearing a car payment can boost your approval more than a raise.

TDS is always the higher of the two ratios, and it's where most borrowers run out of room. Paying down consumer debt before you apply directly increases the mortgage you qualify for. Run your numbers in the affordability calculator.

4. Your loan-to-value (LTV)

Loan-to-value is your mortgage amount divided by the home's value, expressed as a percentage. Put 20% down and your LTV is 80%. Below 20% down, your mortgage is "high-ratio" and requires default insurance (CMHC, Sagen, or Canada Guaranty), which adds a premium to the loan.

A lower LTV means less risk for the lender, often a better rate, and no insurance premium once you cross the 20%-down line. Use the down payment calculator to see how much you need and how your LTV changes as you save more.

5. The stress-test qualifying rate

The mortgage stress test requires you to qualify at the greater of your contract rate plus 2% or the 5.25% minimum qualifying rate. So if your offered rate is 4.5%, you must prove you could afford payments at 6.5%. This sets your true borrowing ceiling.

The stress test applies to federally regulated lenders (the big banks and most monoline lenders). It's why your pre-approval amount is lower than a simple payment calculation suggests. See exactly how it affects you with the stress test calculator.

Frequently asked questions

Which of these 5 numbers matters most?

None works in isolation — lenders check all five together. But TDS and the stress-test rate set the hard ceiling on how much you can borrow, while your credit score most affects the rate you're offered. A weak number in any one area can sink an otherwise strong file.

What credit score do I need for a mortgage in Canada?

Most prime lenders look for around 680 or higher for the best rates. Approvals are possible with lower scores through alternative lenders, usually at a higher rate, with the option to move to prime once your credit improves.

How is the stress-test rate calculated in 2026?

You must qualify at the greater of your contract rate plus 2% or the 5.25% minimum qualifying rate, whichever is higher. The stress test calculator applies the rule to your specific numbers.

Can I improve these numbers quickly?

Some, yes. Paying down a credit card or car loan lowers TDS within a billing cycle, and a larger down payment lowers both your LTV and GDS immediately. Credit-score gains take longer — usually a few months of on-time payments and lower balances.

Want to know your real qualifying numbers? You can ask Maya, our mortgage assistant, to walk you through all five in plain language, then connect with an advisor who'll find the lender whose rules fit your file. Ready to move? Start your application.