This mortgage affordability calculator answers the question a lender answers before a pre-approval: what is the most a home can cost on this income, with these debts and this down payment? It applies the same tests a Canadian lender must apply, the stress test, the gross and total debt service ratios, the minimum down payment and the insured price cap, and it shows which of them sets the limit, so it also works as a mortgage qualification calculator. Every result is computed in the browser, and the numbers entered are not sent or stored.
How do you use this mortgage affordability calculator?
The core inputs come first; the advanced section only matters for some buyers.
- Enter gross household income. Use income before tax for everyone who will be on the mortgage, the way a lender counts it.
- Enter the down payment available. Only the money that will go into the purchase: land transfer tax, legal fees and moving costs come from other savings.
- Enter the interest rate quoted and the amortization. The calculator turns the rate into the qualifying rate automatically, so there is no need to add the stress test yourself.
- Enter monthly debt payments and card balances. Car loans, student loans and support payments go in the first box; credit card and unsecured line of credit balances go in the second, where lenders count a monthly payment on them even if they are paid in full.
- Enter property tax, heating and condo fees. Property tax can be a percentage of the price (so it grows with the home you are shopping for) or a dollar amount from a listing.
- Open “Buyer situation and lender limits” to say whether you are a first-time buyer or buying a new build (this decides whether a 30-year insured amortization is allowed), pick the province (for the tax on the insurance premium) and, if you like, set more cautious debt ratio limits of your own.
- Read the summary and the binding limit first. The four tables then show which rule stopped the price, how the maximum moves with the rate, the income needed for common prices, and the monthly costs at the maximum. The Decision Brief under the result explains the number from its parts.
How much house can I afford? A worked example
Take a first-time buyer in Ontario with $120,000 of gross household income, $80,000 saved for the down payment, a 4.5% five-year fixed rate, a 25-year amortization, a $400 monthly car payment, property tax estimated at 1% of the price a year and $120 a month for heating. These are example figures, not a forecast; use a real quote in the calculator above.
- Monthly income: $10,000, so the GDS limit is $3,900 a month and the TDS limit is $4,400.
- Qualifying rate: the higher of 6.5% or 5.25%, so 6.5%. At that rate each $100,000 borrowed over 25 years counts as $669.82 a month, against $553.47 at the real rate.
- Maximum price: about $559,807. The $80,000 down payment is 14.3% of that, so the loan before insurance is $479,807, a 85.7% loan-to-value ratio.
- CMHC premium: 3.1% of the loan for that band, $14,874, added to the mortgage for a total of $494,681. Ontario’s 8% tax on the premium, $1,190, is due in cash at closing.
- Gross debt service at the maximum: a $3,313.49 tested payment, plus $466.51 of property tax and $120 of heat, is $3,900: exactly 39% of income. GDS is the binding limit.
- Total debt service at the maximum: the same $3,900 plus the $400 car payment is $4,300, or 43%, under the 44% limit. TDS alone would allow about $572,728.
- Real payment: at the 4.5% contract rate the monthly payment on $494,681 is $2,737.93, about $576 less than the payment the lender tested.
The down payment is not what limits this buyer: $80,000 would meet the minimum on a home of up to $1,050,000. Income is the constraint, and within income it is GDS, because the $400 of other debts fits inside the $500 gap between the two ratio limits.
How does the affordability maths work?
A lender asks two questions about the monthly budget and two about the down payment, and the calculator asks them the same way.
The budget questions are the debt service ratios. The gross debt service ratio (GDS) is the mortgage payment, property tax, heating and half of the condo fees, divided by gross monthly income. The total debt service ratio (TDS) is the same total plus every other debt payment. For mortgages with government-backed insurance, federal regulations cap them at 39% and 44%. The mortgage payment inside both ratios is not the real payment: it is the payment on the full loan, CMHC premium included, at the qualifying rate over the amortization the loan is allowed to have.
The down payment questions are the minimum down payment tiers and the insured price cap. Under 20% down, the mortgage has to be insured, insurance is only available on homes priced under $1,500,000, and the down payment must be at least 5% of the first $500,000 plus 10% of the rest.
Every one of these tests gets harder as the price rises: the loan grows, the premium band can step up, property tax grows with the price, and the minimum down payment grows. So the calculator can search for the single highest price that passes all four tests at once. It also runs each test on its own, which is where the “Highest price this rule alone allows” column comes from; the lowest of those is the binding constraint and always equals the overall maximum. Many affordability calculators show only the final number; this column is the one that shows what to change: more income helps only when GDS or TDS binds, a bigger down payment helps only when the down payment rules bind (or by removing the premium), and paying off a car loan helps only when TDS binds.
These are the rules the calculator uses:
How to read this table: add the amounts for each portion. At $1,500,000 or more, insurance isn't available and the minimum is 20% of the whole price.
| Portion of the price from | Up to | Minimum down on that portion |
|---|---|---|
| $0 | $500,000 | 5% |
| $500,000 | $1,500,000 | 10% |
Source: How much you need for a down payment — Financial Consumer Agency of Canada; Backgrounder: Delivering the Boldest Mortgage Reforms in Decades (September 24, 2024) — price cap; Backgrounder: Delivering the Boldest Mortgage Reforms in Decades — down payment tiers; Backgrounder: Delivering the Boldest Mortgage Reforms in Decades — 30-year amortization eligibility; Boldest mortgage reforms in decades come into force today (December 15, 2024); Boldest mortgage reforms in decades come into force today — insured switches at renewal; CMHC Purchase — product page (maximum price, amortization, debt service ratios); Minimum qualifying rate for uninsured mortgages — OSFI; OSFI exempts uninsured mortgage straight switches from the prescribed MQR (November 21, 2024); “Straight Switches” and portfolio insurance (backgrounder, December 2024); Calculating GDS / TDS — CMHC; Calculating GDS / TDS — CMHC (qualifying rate for insured loans); Preparing to get a mortgage — Financial Consumer Agency of Canada (stress test); Insurable Housing Loan Regulations (SOR/2012-282), s. 5 high ratio loans — Justice Laws (current to 2026-09-21, CMHC-insured loans); Insurable Housing Loan Regulations (SOR/2012-282), s. 5(1.1) — 30-year amortization; Eligible Mortgage Loan Regulations (SOR/2012-281), s. 5 high ratio loans — Justice Laws (current to 2026-09-21, private insurers with the government guarantee); Canada Gazette Part II, SOR/2025-55 (Regulatory Impact Analysis Statement) — effective dates; Canada Gazette Part II, SOR/2025-55 — 30-year amortization limited to high-ratio loans. In effect from December 16, 2024; checked September 29, 2026.
How to read this table: find the band that covers the loan divided by the price. The last row applies only to a borrowed down payment, which this calculator does not model.
| Loan-to-value up to | Premium (share of the loan) |
|---|---|
| 65% | 0.6% |
| 75% | 1.7% |
| 80% | 2.4% |
| 85% | 2.8% |
| 90% | 3.1% |
| 95% | 4% |
| 95% | 4.5% |
Source: Mortgage loan insurance premiums (homeowner and small rental loans) — CMHC; Mortgage loan insurance premiums — CMHC (portability surcharge and provincial sales tax); Mortgage loan insurance premiums — CMHC (Refinance schedule note); CMHC Mortgage Loan Insurance cost (consumer page) — CMHC; CMHC Purchase — product page (25-year maximum amortization, premium schedule); CMHC Home Start — product page (30-year amortization premium schedule); CMHC Home Start — eligibility (first-time buyer or newly built; high-ratio only); CMHC Revises Homeowner Mortgage Loan Insurance Premiums (notice, June 5, 2024); Boldest mortgage reforms in decades come into force today (December 15, 2024). In effect from December 15, 2024; checked September 29, 2026.
The debt ratio inputs follow CMHC’s published method: property tax and heating in full, 50% of condo fees, a monthly payment of 3% of credit card and unsecured line of credit balances, and the payment on the loan including the premium. Interest compounds semi-annually, the Canadian convention for fixed-rate mortgages, so the payment per dollar is slightly lower than a US-style calculator would show.
Which limit sets the maximum price for different buyers?
The binding constraint changes from one household to the next, which is why a single “you can afford X” number hides the most useful information. These profiles all use the calculator’s engine with a 4.5% rate, a 25-year amortization, property tax at 1% of the price, $120 of heating and an Ontario first-time buyer.
| Profile | Income | Down payment | Debts counted | Maximum price | Binding limit |
|---|---|---|---|---|---|
| Worked example | $120,000 | $80,000 | $400 car payment | $559,807 | GDS |
| Same, plus a bigger car loan and card balances | $120,000 | $80,000 | $900 + 3% of $5,000 | $489,804 | TDS |
| Same as the example, buying a condo | $120,000 | $80,000 | $400, plus half of $500 condo fees | $528,669 | GDS |
| Smaller income | $90,000 | $40,000 | $400 car payment | $394,902 | TDS |
| High income, small savings | $250,000 | $30,000 | $400 car payment | $550,000 | Minimum down payment |
| High income, mid-size savings | $400,000 | $200,000 | None | $1,499,999 | Insured price cap |
How to read this table: each row changes one or two inputs from the worked example. Moving the car payment from $400 to $900 and adding card balances costs $70,003 of buying power and switches the binding limit from GDS to TDS. The condo fees cost $31,138 even though only half of them count. In the last two rows income is not the problem at all: the $250,000 earner’s income alone would support about $1,053,142, but $30,000 is only the minimum down payment on $550,000. The last household would need 20% down, $300,000, to buy at $1,500,000 or more, because insurance stops there.
How does the interest rate change what I can afford?
The rate matters twice: it sets the real payment, and it sets the qualifying rate that the lender tests. For the worked example:
| Contract rate | Qualifying rate | Maximum price | Mortgage (incl. premium) | Real monthly payment |
|---|---|---|---|---|
| 3.5% | 5.5% | $601,062 | $537,215 | $2,682.15 |
| 4% | 6% | $579,793 | $515,287 | $2,710.51 |
| 4.5% (example) | 6.5% | $559,807 | $494,681 | $2,737.93 |
| 5% | 7% | $541,019 | $475,311 | $2,764.43 |
| 5.5% | 7.5% | $524,512 | $456,958 | $2,789.23 |
| 6.5% | 8.5% | $492,149 | $423,689 | $2,837.97 |
How to read this table: each half-point on the rate moves the maximum price by roughly $19,000 here. Notice the last column: as the rate rises, the maximum mortgage shrinks but the real payment still creeps up, because the lender’s limit is on the tested payment, not the real one. Below a contract rate of 3.25%, the qualifying rate stops at the 5.25% floor, so a lower rate would not raise the maximum at all. The mortgage stress test guide covers who has to pass the test and the exemption for a straight switch at renewal.
How much income do I need to buy a $500,000 home?
Working backwards is often more useful than working forwards. This table uses the worked example’s rate, debts, property tax and heating, and shows the gross household income needed to pass both ratios at two down payments: the legal minimum and 20%.
| Home price | Minimum down payment | Income needed (minimum down) | 20% down | Income needed (20% down) |
|---|---|---|---|---|
| $400,000 | $20,000 | $95,468 | $80,000 | $81,731 |
| $500,000 | $25,000 | $118,327 | $100,000 | $98,953 |
| $600,000 | $35,000 | $140,182 | $120,000 | $118,005 |
| $700,000 | $45,000 | $162,037 | $140,000 | $137,057 |
| $800,000 | $55,000 | $183,892 | $160,000 | $156,109 |
| $1,000,000 | $75,000 | $227,602 | $200,000 | $194,214 |
| $1,200,000 | $95,000 | $271,312 | $240,000 | $232,318 |
How to read this table: the gap between the two income columns is the cost of the smaller down payment in income terms. On a $600,000 home it is about $22,177 of gross income, because the larger loan carries a CMHC premium and has to pass the same ratio limits. The results page rebuilds this table with the reader’s own rate, debts and home costs. Saving the down payment in a First Home Savings Account, up to $8,000 a year and $40,000 over a lifetime, is one way to close that gap; the FHSA contribution limit guide explains carry-forward room.
Is the lender’s maximum a comfortable budget?
The ratios are a ceiling, not a recommendation. They use gross income, so income tax, CPP and EI contributions and workplace deductions come out of the same paycheque before the mortgage does, and they leave out home insurance, maintenance, electricity and water, childcare and saving for retirement. The calculator’s “My own, more cautious limits” option recomputes everything with lower ratios. For the worked example, limits of 32% GDS and 40% TDS lower the maximum from $559,807 to $470,372, and the real monthly payment from $2,737.93 to $2,221.10.
| Budget | GDS limit | TDS limit | Maximum price | Mortgage (incl. premium) | Real monthly payment |
|---|---|---|---|---|---|
| Insured maximums | 39% | 44% | $559,807 | $494,681 | $2,737.93 |
| Cautious limits (reader’s choice) | 32% | 40% | $470,372 | $401,302 | $2,221.10 |
How to read this table: the first row is roughly what a lender could approve; the second is a price that leaves more room in the monthly budget. Neither is advice: the right cushion depends on job security, other goals and how much of the budget is already committed. The mortgage payment calculator shows the full amortization schedule and the renewal risk for either price.
Does a 30-year amortization or a bigger down payment help more?
Both help, in different ways. For the worked example, the Decision Brief in the results quantifies each lever:
- A 30-year amortization (allowed on an insured mortgage only for first-time buyers and new builds) raises the maximum to about $588,392, even though CMHC’s premium rises to 3.3% for the longer amortization. Buyers who are neither first-time buyers nor buying new are held to 25 years when they put less than 20% down.
- $10,000 more down payment raises the maximum by only about $10,169, because GDS still binds; the extra cash mostly replaces borrowing rather than adding to it.
- 10% more gross income raises it by about $50,393, because under GDS 39 cents of every extra dollar of gross income can go to housing costs.
- A rate one point higher cuts it by about $35,295.
When the down payment is close to 20% of the target price, it can be worth checking both sides of the line: at 20% down there is no premium, and an uninsured mortgage is not held to the 25-year insured limit, although the lender still applies the stress test and sets its own maximum amortization.
Common mortgage affordability mistakes
- Testing at the offer rate. Lenders test the payment at the qualifying rate. A budget built on the real payment overstates what will be approved.
- Forgetting that paid-off cards still count. A credit card balance on the statement date counts as a monthly payment of 3% of the balance, even when it is paid in full every month.
- Ignoring condo fees and heating. Half of condo fees and all of the heating cost sit inside both ratios, which can take tens of thousands of dollars off the maximum.
- Spending the whole down payment. Closing costs, land transfer tax and, in Ontario, Quebec and Saskatchewan, the tax on the CMHC premium need cash on top of the down payment. The land transfer tax calculator and the closing costs calculator size those amounts.
- Assuming 30 years is available. With less than 20% down, only first-time buyers and buyers of newly built homes can amortize over more than 25 years.
- Treating the maximum as the target. The ratios use gross income and leave out many real costs; a lower custom limit shows a more comfortable price.
- Carrying consumer debt into the application. When TDS binds, paying down a car loan or line of credit can raise the maximum more than extra savings would. The debt payoff calculator shows how quickly that can happen.
When is it worth talking to a mortgage professional?
This calculator applies the published federal rules to the numbers entered; it cannot see a credit report, verify income or apply a particular lender’s policies. Checking with a licensed mortgage broker or a lender’s mortgage specialist is worth it before making an offer, and especially when income is from self-employment, commission, bonuses or a job held for a short time (common for newcomers), when rental income from a suite should count, when the down payment is gifted or borrowed, when buying a property with two to four units, or when the plan relies on a provincially regulated lender whose rules may differ. A pre-approval sets the rate hold and the maximum in writing. A real estate lawyer or notary confirms closing costs, and a tax professional can help with using an FHSA and the RRSP Home Buyers’ Plan together. This page is education, not financial advice.
Where do the rules in this calculator come from?
The 39% and 44% debt service limits, the qualifying rate, the minimum down payment tiers, the price cap and the amortization limits come from the federal mortgage insurance regulations, the Department of Finance Canada, the Office of the Superintendent of Financial Institutions and the Financial Consumer Agency of Canada. How the ratios are built (half of condo fees, 3% of revolving balances, the premium included in the loan) comes from CMHC’s published method for calculating GDS and TDS, and the premiums and the provincial tax on them come from CMHC and provincial tax authorities. Each rule is stored in a versioned data file with its official source, the date it took effect and the date it was last checked, shown in the sources box on this page. CMHC and the Financial Consumer Agency of Canada also publish their own affordability and mortgage qualifier tools, which can be used to cross-check a result.