Commercial Real Estate DSCR in Canada: How Lenders Calculate Your Maximum Loan

DSCR compares the net operating income available from a property with the annual principal and interest required on its debt:

DSCR = Net Operating Income ÷ Annual Debt Service

If a property produces $400,000 of lender-accepted net operating income and requires $320,000 of annual mortgage payments, its DSCR is 1.25x. In plain language, the property generates $1.25 of operating income for every $1.00 of debt service.

A ratio above 1.00x indicates a cushion. A ratio of exactly 1.00x means all NOI is consumed by debt service, leaving no room for a vacancy, repair, tax increase or other disruption. Lenders therefore normally require a margin above 1.00x.

There is no universal Canadian DSCR requirement. The threshold depends on the lender, property type, tenant quality, lease profile, location, borrower strength and overall risk. A lender may also test coverage using a higher qualifying rate or a shorter amortization than the note terms.

For general background, see BDC's overview of the debt service coverage ratio.

Once accepted NOI and the required DSCR are known, the lender can calculate the maximum annual debt service:

Maximum annual debt service = Accepted NOI ÷ Required DSCR

Assume a property has an appraised value of $6 million, accepted NOI of $400,000 and a required DSCR of 1.25x. The maximum annual debt service is $320,000. If an illustrative mortgage rate of 6.25% and a 25-year amortization support approximately $4 million of principal at that payment, DSCR limits the loan to roughly $4 million.

Now compare that result with a 75% loan-to-value limit. Seventy-five percent of $6 million is $4.5 million. Although the value test permits $4.5 million, the cash-flow test supports only about $4 million. The lower amount normally governs.

This example is illustrative only. Actual proceeds depend on lender calculations, payment frequency, fees, stress assumptions and other underwriting requirements.

Commercial lenders often consider three complementary tests.

• Debt service coverage ratio: Can property income service the proposed payments with an adequate cushion?
• Loan-to-value ratio: How much of the property's appraised value is being financed?
• Debt yield: What return would the lender receive on its loan amount before financing costs, calculated as NOI divided by loan principal?

Each test measures a different risk. DSCR is sensitive to the interest rate and amortization. LTV depends on an appraisal and can move with market capitalization rates. Debt yield relates property income directly to the lender's exposure. The most restrictive test may determine proceeds.

Canadian federally regulated institutions also manage commercial real estate exposure within broader risk frameworks. OSFI's commercial real estate risk management guidance provides useful context on prudent underwriting and portfolio oversight.

• Using gross rent instead of net operating income.
• Ignoring vacancy, bad debt or upcoming lease expiries.
• Leaving out a market management fee because the owner self-manages.
• Treating major recurring repairs as entirely discretionary.
• Assuming the lender will accept every forecast rent increase.
• Calculating payments at the quoted rate when the lender uses a stress rate.
• Confusing property NOI with cash flow after income tax, depreciation or financing costs.
• Focusing on LTV while overlooking the cash-flow constraint.

A credible lender package should make the assumptions visible and reconcile them to leases, operating statements, tax bills, insurance and other supporting records.

Maximum leverage can preserve equity, but it also reduces the cushion available for vacancies, repairs, capital projects and interest-rate changes at renewal. A transaction should be structured around the borrower's objectives and the property's realistic operating range.

Sometimes the better answer is a smaller first mortgage, additional equity, a staged advance, a separate capital-expenditure facility or a different lender whose underwriting better fits the asset. The goal is not merely to close—it is to create a structure the borrower and property can sustain.