How much mortgage can I actually qualify for? Enter your household income, the down payment you have saved, and your debts, and this calculator works out the most expensive home a lender could approve at the stress-test rate — with the CMHC premium included when your down payment is under 20%.
How much mortgage can I actually qualify for?
How the affordability test works
Lenders do not qualify you at the rate you will actually pay. They qualify you at the stress-test rate: the higher of your contract rate plus 2% and 5.25%. Two ratios are then checked on your gross household income. The gross debt service ratio (GDS) is your housing costs — the stress-test mortgage payment, property tax, heating, and half of any condo fees — divided by gross monthly income, and it must be 39% or less. The total debt service ratio (TDS) adds your other monthly debts, and it must be 44% or less. Whichever ratio hits its limit first is the binding constraint on the price you can afford.
The down payment has rules of its own. With mortgage insurance, the minimum is 5% of the first $500,000 of the price plus 10% of the rest. If your down payment is under 20%, a CMHC insurance premium is added to the mortgage: 4.00% of the loan when the loan is more than 90% of the price, 3.10% when it is 85% to 90%, and 2.80% when it is 80% to 85%. At $1,500,000 or more, mortgage insurance is not available at all, so a down payment of at least 20% is required. For an insured mortgage (less than 20% down), a 30-year amortization is limited to first-time buyers and new-build purchases. With 20% or more down (uninsured), a 30-year amortization is generally available.
Assumptions
This calculator assumes a single mortgage with Canadian semi-annual compounding, the CMHC premium tiers above, property tax estimated at 1% of the price per year when the estimate box is checked, heating of $150 a month (the CMHC convention), 50% of condo fees counted, and credit card balances converted to a monthly payment at 3% of the balance. It does not include moving costs, legal fees, or land transfer tax, which are cash you need on top of the down payment. It is a planning estimate, not a lender approval.
Frequently asked questions
What is the stress test?
The stress test qualifies you at the higher of your contract rate plus 2% and 5.25%. It checks that you could still afford the mortgage if rates rise; it does not change the payment you actually make.
What is the difference between GDS and TDS?
GDS covers housing costs only: the stress-test mortgage payment, property tax, heating, and half of condo fees. TDS adds your other debts, such as car payments, student loans, and credit cards. GDS must be 39% or less and TDS 44% or less for an insured mortgage.
What is the minimum down payment in Canada?
With mortgage insurance, 5% of the first $500,000 of the price plus 10% of the rest. On a $600,000 home that is $35,000. At $1,500,000 or more, insurance is not available, so the minimum is 20%.
Why does the CMHC premium change my maximum price?
When your down payment is under 20%, the premium is added to the mortgage, so you borrow more and the stress-test payment is higher. That lowers the price that fits inside the GDS and TDS limits.
Does a car payment really reduce what I can borrow?
Yes. Other monthly debts count in the TDS ratio. A $600 a month car payment uses up part of the 44% TDS room, so the maximum price falls and TDS usually becomes the binding constraint.
Methodology and sources
Methodology: The maximum price is found by bisection on the shared mortgage engine — Canadian semi-annual compounding, the CMHC premium tiers, and the qualifying rate of the higher of the contract rate plus 2% and 5.25%. The solution price must also satisfy its own down-payment rule: the down payment entered must be at least the insured minimum for that price, or at least 20% at $1,500,000 or more. Check: a $600,000 home with $35,000 down at 4.50% over 25 years has a $565,000 loan, a loan-to-value of 94.2%, a CMHC premium of 4.00% ($22,600), a mortgage of $587,600, and a payment of $3,252.21 a month — the same figures the Mortgage Calculator produces for those inputs. GDS and TDS limits of 39% and 44% are the CMHC insured-mortgage limits. Source: CMHC — Mortgage Loan Insurance Cost. The stress-test rules are set out in OSFI Guideline B-20.
2026 rules · Verified November 9, 2026
How we keep this calculator honest: This calculator is built on the published CMHC premium tiers and the OSFI B-20 stress-test rate, and its worked example reproduces the Mortgage Calculator result for the same inputs. If a lender uses different limits for an uninsured mortgage, the result will differ.
Your numbers never leave this page. This calculator runs entirely in your browser — nothing you enter is stored or sent anywhere.
General information only — not financial advice. Your lender will confirm what you can borrow based on your full application and credit history.
Related tools
Once you know what you can afford, work out the monthly payment with the Canadian Mortgage Calculator, the tax on the purchase with the Land Transfer Tax Calculator, the cash you need on closing day with the Closing Costs Calculator, and the rent-or-buy comparison with the Rent vs Buy Calculator.