- Interest Rate
- Down Payment
- Underwriting
- Multifamily
- Secondary Suite
Most investors start with residential mortgages. At some point — usually around property four to eight — the residential system stops working. Your debt ratios are maxed. The stress test kills your buying power. A 12-unit apartment building won’t fit a residential program.
That’s when commercial financing enters the picture. Here’s a clear, side-by-side breakdown of how the two systems differ and when it makes sense to switch.
For a deep dive into how commercial mortgages work — including DSCR calculations, NOI analysis, property types, and lender types — see our full guide on how commercial mortgages work in Canada.
The Full Comparison at a Glance
| Feature | Residential Mortgage | Commercial Mortgage |
|---|---|---|
| Property types | 1–4 units | 5+ units, office, retail, industrial |
| Qualification method | Personal income + stress test | Property income (DSCR / NOI) |
| Stress test | Yes — qualify at contract rate + 2% or 5.25% floor | No federal stress test |
| Down payment | 5–20% (insured/uninsured) | 5–50% (varies by type and program) |
| Interest rates | Lower (insured from ~4–5%) | Typically 0.5–2% above residential |
| Amortization | 25–30 years | 20–50 years (CMHC MLI Select up to 50) |
| Term length | Typically 5 years | 3–10 years |
| Personal guarantee | Always | Usually required, sometimes limited |
| Lender options | Banks, credit unions, monolines | Banks, credit unions, life companies, private |
| Appraisal method | Comparable sales | Income approach (cap rate / NOI) |
| Closing timeline | 30–45 days | 45–90 days |
| Prepayment flexibility | 10–20% annual typically | Often more restricted |
Find Out If Your Property Qualifies
The Key Distinction: How Qualification Works
Residential: Your Income Is the Ceiling
Residential lenders calculate your GDS and TDS ratios based on personal income, then apply the stress test — qualifying you at the higher of 5.25% or your contract rate plus 2%. Your personal income puts an absolute ceiling on borrowing, regardless of how well your properties perform.
Most investors hit this wall somewhere between property four and property eight. Adding more residential debt keeps pushing ratios higher until the bank says no.
Commercial: The Property Is What Matters
Commercial lenders ask a different question: does this property generate enough rental income to cover the mortgage and expenses? The key metric is the Debt Service Coverage Ratio (DSCR) — the property’s Net Operating Income divided by annual debt service.
There is no federal stress test on commercial mortgages. An investor with completely maxed residential debt ratios can still qualify for commercial mortgage options available in Canada if the building generates sufficient income. This is how investors break through residential debt ratio limits and keep scaling.
You can test whether a property qualifies using the DSCR loan calculator.
The Four-Unit Ceiling Problem
In Canada, the dividing line is five units. One to four units are residential. Five or more are commercial.
This creates a natural scaling point. Buying one duplex at a time is slow and each purchase eats into personal debt ratios. Switching to six- or eight-unit apartment buildings puts you under commercial rules — where the property’s income, not your personal income, drives qualification.
Counterintuitively, bigger properties can be easier to finance once you cross the five-unit threshold.
Down Payment: The Surprising Reality
For residential investment property mortgages, you need at least 20% down — no CMHC insurance available.
For commercial multi-family under CMHC MLI Select, you may need as little as 5% down with insurance. A 20-unit apartment building with MLI Select can require a lower equity percentage than a single investment duplex under residential rules.
Non-multi-family commercial properties (office, retail, industrial) typically require 25–35% down.
Amortization: The Hidden Commercial Advantage
Residential mortgages cap at 25–30 years. CMHC MLI Select multi-family mortgages can go to 50 years.
On a $3M mortgage at 5%:
- 25-year amortization: ~$17,500/month
- 50-year amortization: ~$13,500/month
That $4,000/month difference improves cash flow and strengthens your DSCR ratio.
Appraisal: Income Creates Value
Residential properties are appraised using comparable sales — you’re at the mercy of the broader market.
Commercial properties are appraised using the income approach: NOI ÷ cap rate = value. Raise rents, reduce vacancies, or cut operating costs, and you directly increase the property’s appraised value. This is called forced appreciation, and it’s one of the most powerful tools in commercial investing.
When to Make the Switch
Your debt ratios are maxed. If your lender says no to another residential mortgage, commercial financing based on property income may solve it.
You want to scale faster. One 12-unit building adds twelve units in a single transaction.
You’re hitting the stress test wall. Commercial mortgages avoid it entirely.
You want more control over value. With commercial, your property value is tied to its income — you can directly influence that number.
You’re comfortable with more complexity. Commercial deals involve longer due diligence, environmental assessments, and more documentation than residential.
Plan Your Switch to Commercial Financing
Key Takeaways:
- The Full Comparison at a Glance
- The Key Distinction: How Qualification Works
- The Four-Unit Ceiling Problem
- Down Payment: The Surprising Reality
- Amortization: The Hidden Commercial Advantage
Frequently Asked Questions
At what number of units does a mortgage become commercial in Canada?
Is the mortgage stress test applied to commercial mortgages?
Are commercial mortgage rates always higher than residential?
Can I qualify for a commercial mortgage without prior commercial experience?
Should I start residential and switch to commercial later?
Disclaimer: This article is for informational purposes only and does not constitute financial advice. Consult a licensed mortgage professional before making any financing decisions.
Written by
LendCity
Published
February 8, 2026
· Updated February 28, 2026Reading time
5 min read
Commercial Mortgage
Financing for commercial properties like retail, office, or multifamily buildings with 5+ units, with different qualification criteria than residential mortgages.
DSCR
Debt Service Coverage Ratio - a metric that compares a property's [net operating income](/glossary/noi) to its mortgage payments. A DSCR of 1.25 means the property generates 25% more income than needed to cover the debt. Lenders typically require a minimum DSCR of 1.0 to 1.25 for investment property loans. See also [Cap Rate](/glossary/cap-rate) and [Cash Flow](/glossary/cash-flow).
NOI
Net Operating Income - the total income a property generates minus all operating expenses, but before mortgage payments and income taxes. Calculated as gross rental income minus [vacancies](/glossary/vacancy-rate), property taxes, insurance, maintenance, and property management fees. NOI is used to calculate both [Cap Rate](/glossary/cap-rate) and [DSCR](/glossary/dscr).
Mortgage Stress Test
A federal requirement to qualify at the higher of your contract rate +2% or the benchmark rate (around 5.25%). For investors, rental income can be used to offset this calculation, though lenders typically only count 50-80% of expected rent.
LTV
Loan-to-Value ratio - the mortgage amount expressed as a percentage of the property's appraised value or purchase price (whichever is lower). An 80% LTV means you're borrowing 80% and putting 20% [down](/glossary/down-payment). Lower LTV generally means better [interest rates](/glossary/interest-rate) and terms. See also [Equity](/glossary/equity) and [Leverage](/glossary/leverage).
Amortization
The period over which a mortgage is scheduled to be fully paid off through regular payments of principal and [interest](/glossary/interest-rate). In Canada, common amortization periods are 25 or 30 years, though the mortgage term (when you renegotiate) is typically 1-5 years. A longer amortization lowers monthly payments, improving [cash flow](/glossary/cash-flow) but increasing total interest paid.
Hover over terms to see definitions. View the full glossary for all terms.