Mortgage Affordability Calculator — Canada 2026
Enter any home price and instantly see the income required, down payment needed, and whether you'd pass the OSFI stress test — comparing the tiered legal minimum, 10%, and 20% down simultaneously.
The mortgage stress test means most Canadian buyers qualify for 20–25% less than they expect. See where you stand.
"How much can I afford?" is the most-Googled mortgage question, and the answer most calculators give is wrong. They tell you what monthly payment fits your income at your contract rate. Canadian lenders don't qualify you that way. They run your file at the OSFI stress-test rate — the greater of 5.25% or your contract rate plus 2 percentage points — which on a 4.29% mortgage means qualifying at 6.29%. That single rule trims roughly 20% off what a generic calculator says you can afford. If you walk into a bank with a US-style affordability number, you'll come out with a smaller pre-approval than you expected.
This calculator does the math the way a Canadian underwriter does it: it runs the stress-test rate, applies GDS (gross debt service, capped at 39%) and TDS (total debt service, capped at 44%) ratios against your income and debts, layers in property tax and heating, and tells you the maximum price you'd actually qualify for. It also shows you three down-payment scenarios at once — legal minimum, 10%, and 20% — so you can see how saving more changes the equation.
How Canadian Affordability Math Actually Works
A Canadian lender approves a mortgage when three conditions are all true: your down payment meets or exceeds the legal minimum (tiered: 5% up to $500K, then 10% on the portion to $1.5M, then 20% above), your GDS ratio at the qualifying rate is at or under 39%, and your TDS ratio at the qualifying rate is at or under 44%. Miss any one of these and the deal doesn't close. Most affordability calculators online only check the third (or worse, only the monthly payment), which is why their answers are systematically too generous.
The qualifying rate (not the contract rate)
Lenders calculate your hypothetical monthly mortgage payment using the OSFI qualifying rate. If your contract rate is 4.29%, your qualifying rate is 6.29%. If your contract rate is 3.10%, your qualifying rate is 5.25% (the floor). The qualifying rate is what the lender uses to compute your GDS/TDS ratios. The contract rate is what you actually pay each month after the deal closes. Borrowers who don't understand this distinction sometimes submit budgets to lenders showing they can afford the contract-rate payment, then are confused when the application is declined for failing the qualifying-rate ratios.
GDS — Gross Debt Service ratio (cap: 39%)
GDS measures how much of your gross (pre-tax) monthly income goes to housing. It includes:
- Mortgage payment calculated at the qualifying rate, not your contract rate
- Annual property tax divided by 12
- Heating cost (CMHC default $150/month if not otherwise specified)
- 50% of monthly condo fees if applicable
That total divided by your gross monthly income must come in at 39% or less. Lenders may approve insured borrowers up to 39% GDS as a hard ceiling, with stronger files often coming in well below.
TDS — Total Debt Service ratio (cap: 44%)
TDS adds every other monthly debt obligation to the GDS calculation: car loans, student loans, lines of credit, credit-card minimum payments (or in some cases 3% of the outstanding balance), child support, alimony. The same cap applies to the same denominator: the total housing-plus-debt monthly cost cannot exceed 44% of your gross monthly income.
You must pass both GDS and TDS to qualify. For a borrower with no other debts, GDS is usually the binding constraint. For a borrower carrying a car payment plus a student loan plus a line of credit balance, TDS is usually the binding constraint, and adding more debt before applying directly reduces the home you can afford.
You earn $120,000/year ($10,000/month gross). You have no car loan, no student debt, and no lines of credit. You're targeting a $700,000 home with the legal minimum down payment of $45,000 (6.43%).
This buyer doesn't qualify for the $700K home. Their GDS is well over the 39% limit. To qualify, they'd need to either reduce the target price to roughly $580,000–$600,000 (the income-determined ceiling), increase down payment significantly (which reduces the qualifying mortgage payment), increase income, or extend the amortization to 30 years if eligible (first-time buyer or new build).
What "qualified" actually feels like in dollars
Roughly speaking, after the stress test, every $1,000 of household income per month supports about $4,000–$5,000 of qualifying mortgage. So a household at $10,000/month (≈ $120K/year) supports a qualifying mortgage of roughly $400,000–$500,000, which (at 7% effective down payment) translates to a home price ceiling around $560,000–$640,000. Carrying $500/month in other debts knocks $60,000–$80,000 off the qualifying purchase price. Carrying $1,000/month in other debts knocks roughly $130,000–$170,000 off.
Income Required at Different Price Points (Approximate)
| Home Price | Min Down (Tiered) | Approx. Income Needed (No Debts) | Approx. Income Needed ($500/mo Debts) |
|---|---|---|---|
| $500,000 | $25,000 | ~$95,000 | ~$112,000 |
| $600,000 | $35,000 | ~$112,000 | ~$132,000 |
| $700,000 | $45,000 | ~$132,000 | ~$155,000 |
| $850,000 | $60,000 | ~$160,000 | ~$188,000 |
| $1,000,000 | $75,000 | ~$190,000 | ~$222,000 |
| $1,200,000 | $95,000 | ~$225,000 | ~$262,000 |
| $1,500,000+ | 20% required | ~$240,000+ | ~$278,000+ |
Approximate qualifying income at the legal minimum down payment, 4.29% contract rate (6.29% qualifying), 25-year amortization, GTA-typical property tax (~0.85% of price), CMHC default $150/month heating, GDS-binding case. Real qualification varies with credit profile, lender overlays, and condo fees. See income needed to buy a house in Canada for the full breakdown.
The leftmost column is the approximate household income — single or dual — required to clear the GDS test at that price with the legal minimum down payment and no other debts. The right column shows what happens when you carry a typical $500/month debt load (a car payment, a student loan, or a small line-of-credit balance). Adding $500/month in debt service costs you roughly $20,000 of qualifying income at every price point. This is why mortgage advisors universally recommend paying down or restructuring revolving debts before applying — every dollar of debt cleared roughly translates to $4 of additional qualifying mortgage.
Three Levers That Change Your Affordability
If the calculator says you don't qualify for the home you want, you have exactly four levers to pull. Listed in order of typical impact:
- Eliminate or reduce other monthly debts. Each $100/month in monthly debt obligations costs you roughly $13,000–$16,000 in qualifying purchase price. Paying off a $5,000 credit card balance at $250/month minimum payment buys you back ~$30,000 of affordability. This is usually the highest-leverage move.
- Increase income. Adding a co-applicant doubles (or partially adds, depending on the type) the income side of the ratios. Be cautious here — adding a co-applicant who carries their own significant debt can hurt rather than help.
- Increase the down payment. A larger down payment lowers the qualifying mortgage amount, which lowers the qualifying monthly payment, which improves the GDS/TDS ratios. The leverage isn't 1:1 — adding $30,000 to your down payment doesn't add $30,000 to your qualifying purchase price; it usually adds something closer to $25,000–$35,000 depending on whether you also avoid CMHC.
- Extend amortization to 30 years (if eligible: first-time buyer or new-build buyer on insured mortgages, anyone on conventional 20%+ down). The longer amortization lowers the qualifying monthly payment and meaningfully improves your GDS/TDS ratios — typically buying you 10–15% more qualifying purchase price. Trade-off: substantially more total interest over the life of the loan.
How Different Income Types Are Treated
Lenders don't treat all income the same. The number on your tax return isn't always the number a lender uses to qualify you.
- Salaried T4 income — counted at 100%. Easiest to verify (recent pay stubs, NOA, employment letter), and the cleanest qualification path. If you have a 3-month probationary period clause, some lenders won't count the income until probation completes.
- Variable income (commissions, bonuses, overtime) — typically averaged over the most recent 2 years if it's recurring. A first-year commission earner with no track record may have only their base salary counted. Consistent 2+ year history is what unlocks full inclusion.
- Self-employed income — most lenders use the 2-year average of net business income from your T1 General (lines 13499–13899) plus any add-backs the lender allows (depreciation, business-use-of-home portions, etc.). Stated-income programs exist but typically require 25–35% down. Many self-employed buyers benefit from working with a broker who knows the BFS-friendly lenders.
- Rental income — varies. Some lenders count 50%, some 80%, some require a 2-year history on tax returns showing the rental was profitable. Investment properties have different rules entirely (DCR — debt coverage ratio).
- RRIF / pension / investment income — typically counted at 100% if it's stable and verifiable. Investment income from a non-registered portfolio is often counted at a discount or excluded entirely.
- Spousal/child support received — counted with proper documentation (court order, separation agreement, demonstrated 6–12 months of receipt). Not counted if it's informal.
- Foreign income — generally not accepted by major Canadian banks. Some specialty lenders accept it with significant documentation, often at 25%+ down.
If your income is anything other than straight T4 salary, talk to a broker before assuming a calculator's output applies to you. The Income Qualifier tool inside ClearKey models several of these income types — see the Income Qualifier tab.
Common Mistakes to Avoid
The single most common error. Your monthly payment is calculated on the contract rate, but the lender approves you on the qualifying rate. A $4,000/month qualifying-rate payment translates to roughly a $3,300/month contract-rate payment in current rates — a $700/month gap. Buyers who budget around the lower number get approved for less than they expected.
GDS includes 50% of condo fees and 100% of monthly property tax. A $700,000 condo with $600/month maintenance fees and $4,800/year property tax adds ~$700 to your qualifying housing cost — about $1,800 less qualifying mortgage and roughly $25,000 less qualifying purchase price. Most affordability calculators ignore one or both.
Lenders typically count 3% of outstanding credit-card and line-of-credit balances as monthly debt service. A $20,000 line-of-credit balance contributes $600/month to your TDS calculation — even if you only pay the minimum each month. Carrying revolving debt into a mortgage application is one of the fastest ways to fail TDS. Pay it down or pay it off before applying.
The 39%/44% caps are CMHC's defaults. Individual banks and B-lenders apply tighter internal limits to weaker files (35%/42%, sometimes lower) or looser limits to stronger files. Two lenders running the exact same application can come back with different "yes/no" answers. Pre-approval at one lender doesn't mean every lender will approve.
A pre-approval verifies your income and credit but doesn't approve a specific property. Final approval requires the property to appraise at value, pass the lender's property-type rules (some lenders won't lend on certain condos, lofts, or rural properties), and have no condo-status-certificate issues. Roughly 5–10% of pre-approved offers fall through at final underwriting. Always have a financing condition in your offer unless your situation is rock-solid.
What This Calculator Doesn't Tell You
This is an educational starting point, not an underwriting decision. It deliberately doesn't model:
- Your specific lender's overlays. Different lenders apply different debt servicing, credit-score, and property-type rules. Some are tighter than CMHC defaults, some are looser. The only way to know your specific approval is to apply.
- Self-employed BFS programs. Stated-income, alternative-doc, and B-lender programs change the qualification math entirely. This calculator assumes T4 income.
- Bridge financing. If you're selling one home and buying another, your closing-day cash flow is materially different from the standalone affordability number this calculator produces.
- Closing-day cash-on-hand. Affordability is a monthly-flow concept. Down payment + closing costs is a one-time-cash concept. You can pass affordability and still not have enough cash to close. Use the down payment calculator for the cash-on-hand picture.
- Future rate changes for variable-rate borrowers or upcoming renewals. The qualifying rate is a snapshot; if rates change, your future qualification picture changes too.
How Much Income Do You Need to Buy a House in Canada?
Your income is the ceiling on what you can borrow. A household earning $120,000 with minimal debt qualifies for roughly $580,000–$620,000 after the stress test. Every $500/month in existing debt payments costs you $60,000–$80,000 in purchasing power. See the full breakdown at every price point in our income needed to buy a house in Canada guide.
Ready to see your numbers? ClearKey runs the full stress test, calculates CMHC premiums, and shows you exactly what you need to qualify.
Open Full Calculator →Frequently Asked Questions
What's the difference between the qualifying rate and the contract rate?
The contract rate is the rate your lender actually charges you and the rate your monthly payment is calculated on. The qualifying rate is what the lender uses to test whether you'd still afford the mortgage if rates rose. The qualifying rate is the greater of 5.25% or your contract rate plus 2 percentage points — set by the OSFI B-20 stress test. Your monthly payment after closing is calculated on the contract rate; the qualifying rate is only used for approval.
Why do calculators say I can afford more than the bank approves me for?
Generic calculators usually use your contract rate, ignore property tax, ignore condo fees, ignore other debts, or apply softer GDS/TDS limits. Canadian lenders apply all of these constraints simultaneously plus their own internal overlays. The result: most generic calculators overstate Canadian affordability by 20–40%. Use a calculator that explicitly applies the OSFI stress test and includes property tax and heating in GDS — like this one.
Does paying off my credit card improve my mortgage qualification?
Yes, often dramatically. Lenders typically count 3% of outstanding credit-card and line-of-credit balances as a monthly debt service obligation. Paying off a $20,000 line of credit removes $600/month from your TDS calculation, which translates to roughly $80,000 of additional qualifying purchase price. Paying down (not just paying minimum on) revolving debt is usually the highest-leverage move you can make before a mortgage application.
Does adding a co-applicant always help?
Not always. A co-applicant adds their income to yours, but also adds their debts. If your co-applicant earns $40K and carries $700/month in debts, the math may actually go backwards. Lenders also use the lower of the two credit scores in many cases, so a co-applicant with weaker credit can hurt your rate. Run the math both ways — solo and joint — before deciding.
How long is a mortgage pre-approval good for?
Most pre-approvals are valid for 90 to 120 days, including a rate hold during that window. If rates fall during your hold period, lenders often honour the lower rate; if rates rise, your held rate protects you. After expiry, you re-apply with current information. Pre-approvals are not binding — the lender can decline at final underwriting if anything changes between pre-approval and offer.
Can I qualify for more by extending my amortization to 30 years?
Yes, typically 10–15% more qualifying purchase price. The longer amortization lowers your monthly mortgage payment, which improves your GDS/TDS ratios. As of December 15, 2024, 30-year amortization on insured mortgages is available to first-time buyers OR buyers of newly built homes — either condition qualifies. Conventional (20%+ down) mortgages allow 30-year amortization regardless. The trade-off is substantially more total interest paid over the life of the loan.
Does my credit score affect how much I can afford?
Indirectly. Your credit score doesn't change the GDS/TDS math, but it changes the rate you're offered. A higher rate means a higher qualifying-rate payment, which means a lower qualifying purchase price. The difference between a 760+ score and a 620 score can be 0.30–1.00% in offered rate, which translates to meaningfully different affordability. Below ~620 you may also face B-lender pricing, which adds further premium.
What if I'm self-employed — does this calculator still apply?
The stress-test math is the same, but how your income gets calculated differs. Most lenders use a 2-year average of your T1 net business income with allowable add-backs (depreciation, etc.). Stated-income BFS programs require 25–35% down with rate premiums. The numbers in this calculator are accurate if you enter your accepted business income — but figuring out what that number is for your specific tax situation requires a broker conversation. The Income Qualifier tab in the main ClearKey app models several income types beyond T4.
This calculator is for educational purposes only and does not constitute financial, mortgage, or legal advice. Results are estimates based on standard Canadian qualification rules and current stress test rates. Income required figures assume current 5-year fixed rate of approximately 4.29%, GTA-typical property tax, and standard CMHC heating defaults — actual qualification varies with credit profile, lender overlays, property type, and market conditions. Always consult a licensed mortgage professional. ClearKey is not a licensed mortgage brokerage.