How much mortgage can I afford in Canada?
A plain-language breakdown of GDS, TDS, and the OSFI stress test — the three rules that decide your maximum mortgage.
Figuring out how much mortgage you can afford is the single most important step before you start house hunting. Canadian banks don't just look at your income — they apply two specific formulas called GDS and TDS, plus a mandatory stress test, to decide your maximum borrowing limit. This guide breaks down exactly how it works, with real numbers, so you know where you stand before you ever talk to a lender.
The two rules every Canadian lender uses
Rule 1 — Gross Debt Service (GDS) ratio
Your GDS ratio measures what percentage of your gross monthly income goes toward housing costs. Canadian lenders require your GDS to be 39% or lower.
GDS includes:
- Monthly mortgage payment (principal + interest)
- Property taxes
- Heating costs
- 50% of condo fees (if applicable)
Example: If your gross household income is $120,000 per year ($10,000/month), your maximum monthly housing costs are $3,900 (39% of $10,000).
Rule 2 — Total Debt Service (TDS) ratio
Your TDS ratio measures all your monthly debt payments as a percentage of gross income. Lenders require TDS to be 44% or lower.
TDS includes everything in GDS, plus:
- Car loan payments
- Student loan payments
- Credit card minimum payments
- Any other debt obligations
Example: Using the same $120,000 income, your total monthly debt payments (including housing) cannot exceed $4,400.
Key takeaway: If you have significant existing debt — car payments, student loans — it directly reduces how much mortgage you can qualify for.
The OSFI stress test — the rule that changes everything
Since 2018, every Canadian mortgage applicant must pass the OSFI stress test, regardless of their down payment size. This means you must qualify at whichever rate is higher:
- Your actual contract rate + 2%, OR
- 5.25% (the OSFI minimum qualifying rate)
Why this matters: If today's 5-year fixed rate is 5.5%, you must prove you can afford payments at 7.5%. This single rule reduces your maximum borrowing power by approximately 20% compared to qualifying at the actual contract rate.
Example: A household qualifying for a $600,000 mortgage at the contract rate would only qualify for roughly $480,000 after the stress test is applied.
How much mortgage can you afford? Real examples by income
The table below shows estimated maximum mortgage amounts for different income levels in Canada, assuming a 20% down payment, 25-year amortization, and current stress test rates. These are estimates — your actual amount depends on your debt load, province, and lender.
| Household income | Max mortgage | Monthly payment |
|---|---|---|
| $60,000 | ~$280,000 | ~$1,560 |
| $80,000 | ~$375,000 | ~$2,085 |
| $100,000 | ~$470,000 | ~$2,610 |
| $120,000 | ~$565,000 | ~$3,140 |
| $150,000 | ~$705,000 | ~$3,920 |
| $200,000 | ~$940,000 | ~$5,225 |
The four factors that determine your maximum mortgage
1. Household income
The higher your combined gross income, the more you can borrow. Most lenders consider base salary, regular overtime, self-employment income (2-year average), and rental income (at 50–80% of gross rent).
2. Existing debt
Every $500/month in existing debt payments (car, student loan, credit card minimums) reduces your maximum mortgage by approximately $100,000. Paying down high-payment debts before applying can significantly increase your borrowing power.
3. Down payment size
Your down payment determines whether you need CMHC mortgage insurance and affects your monthly payment directly. In Canada:
- Less than 20% down → CMHC insurance required (adds 2.8%–4% of mortgage to your loan)
- 20% or more → no CMHC insurance required
- Homes over $1.5 million → minimum 20% down required by law
4. Amortization period
A longer amortization reduces your monthly payment but increases total interest paid. In Canada, the maximum amortization is:
- 25 years for insured mortgages (under 20% down)
- 30 years for uninsured mortgages (20% or more down) as of August 2024
A quick way to estimate your maximum mortgage
Use this simple rule of thumb before using a full calculator:
Your maximum mortgage is approximately 4 to 4.5 times your gross annual household income, assuming you have little to no existing debt.
Examples:
- $80,000 income → approximately $320,000–$360,000 mortgage
- $120,000 income → approximately $480,000–$540,000 mortgage
- $160,000 income → approximately $640,000–$720,000 mortgage
This is a starting estimate only. Your actual limit depends on your debt load, credit score, and lender policies.
How to increase how much mortgage you can afford
If you are not qualifying for the amount you need, here are the most effective strategies:
- Increase your income: Adding a co-borrower (spouse or partner) to the application pools both incomes and is the single fastest way to increase your borrowing limit.
- Pay down existing debts: Eliminating a $400/month car payment before applying can add approximately $80,000–$100,000 to your maximum mortgage.
- Save a larger down payment: A larger down payment reduces your required loan amount and eliminates CMHC insurance costs if you reach 20%.
- Choose a longer amortization: If you have 20% or more down, extending to a 30-year amortization reduces your monthly payment and may help you pass the stress test on a larger amount.
- Improve your credit score: A score above 680 gets you access to the best rates. A score below 600 may limit your lender options significantly.
What Canadian banks won't tell you
The number your bank pre-approves you for is not what you should spend. Banks approve you for the maximum you qualify for — not what is comfortable for your lifestyle. Most financial advisors recommend keeping your actual housing costs at 30–33% of gross income, even if you qualify for 39%.
Buying at your maximum limit leaves no room for:
- Interest rate increases at renewal
- Job loss or income reduction
- Unexpected home repairs
- Starting a family or lifestyle changes
A pre-approval is a ceiling, not a target.
Use Smart Mortgage Calculator to see your real numbers
Instead of guessing, paste any Realtor.ca, Zolo, or MLS listing URL into Smart Mortgage Calculator and get a full breakdown instantly — monthly payment, stress test result, CMHC insurance if applicable, property tax estimate, and closing costs. It takes 30 seconds and shows you the real cost of any home in Canada.
See the real cost of any Canadian home.
Paste any Realtor.ca, Zolo, or MLS listing URL.
Try the calculator — paste any listing URLFrequently asked questions
What credit score do I need for a mortgage in Canada?
Most major banks require a minimum credit score of 680. Some lenders will approve below 680 but at higher rates. Credit unions and alternative lenders may work with scores as low as 550.
Can I get a mortgage with a single income in Canada?
Yes. Single-income applicants qualify using the same GDS/TDS rules. The challenge is that with one income, the maximum borrowing amount is lower. Adding a co-borrower or guarantor is the most effective solution.
Does my down payment source affect my mortgage approval?
Yes. Down payments must be from your own savings, an RRSP Home Buyers Plan withdrawal, or a gift from an immediate family member. Gifted funds must be confirmed with a signed gift letter. Borrowed down payments are not permitted for insured mortgages.
How long does mortgage pre-approval last in Canada?
Most pre-approvals are valid for 90–120 days. After that you must reapply, and your rate hold expires. Pre-approval does not guarantee final approval — lenders still verify the property and your financial situation at time of purchase.
Is the stress test the same at all Canadian lenders?
All federally regulated lenders (major banks) must apply the OSFI stress test. Credit unions in some provinces are provincially regulated and may apply different rules, though most now follow similar guidelines.
This article is for educational purposes only. Mortgage qualification rules change and vary by lender. Always consult a licensed mortgage broker before making real estate decisions.