The short answer: a household earning $100,000 may see a mortgage-only ceiling near $500,000 under favourable assumptions, but property tax, heating, condo fees and existing debt can pull the approval meaningfully lower. The lender qualifies the file at a higher interest rate than the borrower will initially pay.
How the mortgage stress test works
For an uninsured mortgage at a federally regulated lender, OSFI’s minimum qualifying rate is the greater of the contract rate plus 2 percentage points or 5.25%. CMHC applies the same formula to insured qualification. The higher rate is used only to test affordability; the actual payment follows the contract.
For example, a 4.04% contract rate is tested at 6.04%. Rates move quickly: one Ontario market snapshot listed 4.59% for an insured five-year fixed mortgage on October 2, 2026, which would produce a 6.59% qualifying rate. Treat any advertised rate as a dated snapshot, not a quote.
GDS and TDS, in plain English
Gross Debt Service (GDS) is the share of gross household income used for the stress-tested mortgage payment, property tax, heating and 50% of condo fees. Total Debt Service (TDS) adds car loans, student loans, credit cards, lines of credit and other debt payments. CMHC’s insured-mortgage maximums are 39% GDS and 44% TDS; an uninsured lender sets its own underwriting limits.
A worked example
Suppose gross household income is $120,000, or $10,000 per month. The 39% GDS ceiling allows $3,900 for qualifying housing costs. If estimated property tax is $450, heat is $150 and half the condo fee is $250, only $3,050 remains for the stress-tested mortgage payment.
Now add a $550 car payment and $250 of other monthly debt. The 44% TDS ceiling is $4,400; after $800 of debt, just $3,600 remains for all housing costs. In this case GDS still caps the file at $3,900, while TDS allows $3,600 plus the $800 debt. Both tests must pass.
Income-to-mortgage examples
The table isolates income so readers can see the upper boundary. It assumes a 4.04% contract rate, a 6.04% qualifying rate, 25-year amortization, no other debts and the full 39% GDS room going to principal and interest. Real approvals are lower once property tax, heat and condo fees are included.
| Household income | Monthly GDS room | Approx. mortgage ceiling |
|---|---|---|
| $75,000 | $2,438 | $380,000 |
| $100,000 | $3,250 | $506,000 |
| $125,000 | $4,063 | $633,000 |
| $150,000 | $4,875 | $759,000 |
Calculation uses Canadian semi-annual compounding converted to an equivalent monthly rate. The $100,000 scenario explains why rough estimates often show about $500,000–$530,000, but it is not a lender approval.
Toronto reality check: A $1 million home with 20% down leaves an $800,000 mortgage. Depending on the rate, property tax, heat and debt assumptions, a household may need roughly $181,000–$204,000 of gross income. Published estimates vary, so use the property’s actual tax and a current lender rate.
Down payment and insurance rules
For homes up to $500,000, the federal minimum down payment is 5%. From $500,000 to below $1.5 million, it is 5% of the first $500,000 plus 10% of the portion above. A $900,000 home therefore needs at least $65,000 down. The insured-mortgage price cap rose to $1.5 million effective December 15, 2024; at or above that price, at least 20% down is required.
With less than 20% down, mortgage default insurance generally protects the lender, not the buyer, and its premium is typically added to the mortgage. With 20% or more down, the mortgage is usually uninsured. Insured loans can receive sharper rates, but the premium raises the balance; compare total cost, not just the headline rate.
Who can use a 30-year amortization?
Since December 15, 2024, 30-year amortizations on insured mortgages have been available to all first-time homebuyers and all buyers of newly built homes. A longer amortization reduces the required payment and may increase the amount that fits the ratios, but it also keeps the debt outstanding longer and generally increases total interest. Other insured purchases are generally limited to 25 years; uninsured options depend on the lender and product.
What raises—or lowers—your approval
- Raises it: stable verifiable income, a larger down payment, lower monthly debt, a lower qualifying rate and a co-borrower with income.
- Lowers it: car loans, revolving balances, high property tax, condo fees, variable or hard-to-prove income and a higher stress-test rate.
- Credit matters: CMHC material lists 600 as a minimum for at least one borrower, while many prime lenders generally prefer about 680 or better for competitive options.
- Approval is not comfort: lenders do not fully capture maintenance, insurance, childcare, commuting or every household expense in GDS/TDS.
Before making an offer, ask a lender to rerun the file using the property’s taxes, realistic heat, condo fees, current debts and the exact product rate. Lending rules and insurer policies can change.
Frequently asked questions
How much mortgage can I get with a $100,000 income in Ontario?
At a 4.04% contract rate, the mortgage-only ceiling is about $506,000 when tested at 6.04% over 25 years. Property tax, heat, condo fees and debts reduce the actual result, so $500,000–$530,000 is an upper-level illustration rather than a promise.
What mortgage rate do Ontario buyers have to qualify at?
The greater of the contract rate plus 2 percentage points or 5.25%. For example, a 4.59% rate is tested at 6.59%.
How much down payment is required in Ontario?
Use 5% of the first $500,000 and 10% of the portion above that up to below $1.5 million. A home priced at $1.5 million or more requires at least 20% down.
Can I choose a 30-year amortization with less than 20% down?
Eligible first-time homebuyers and buyers of newly built homes may use 30 years on an insured mortgage. Other insured purchases are generally capped at 25 years.
Does a larger down payment always increase approval?
It reduces the mortgage needed, but paying off a monthly debt can sometimes improve TDS more. Ask the lender to compare both uses of the same cash.
Sources and methodology
- OSFI: minimum qualifying rate for uninsured mortgages
- CMHC: calculating GDS and TDS
- Financial Consumer Agency of Canada: down payment rules
- Finance Canada: insured cap and 30-year amortization expansion
- nesto: October 2026 Ontario fixed-rate snapshot
- Ratehub: August 2026 affordability assumptions and rate context
This article provides general information, not financial advice or a mortgage commitment. Estimates vary by lender, property and borrower. Confirm current rates, rules and qualification with your lender or a licensed mortgage professional.