Rental Property
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How rental cashflow works in Canada

A rental's performance comes down to a few numbers that build on each other. Start with effective rent — your gross rent minus a vacancy allowance for the months a unit sits empty. Subtract the operating expenses (property tax, insurance, utilities you pay, management, and a maintenance and capital reserve) and you have Net Operating Income, or NOI. NOI deliberately excludes the mortgage, because it measures how the property itself performs before financing. Take the mortgage payment out of NOI and what is left is your cashflow — the money in your pocket each month, or the shortfall you cover.

From NOI come the two ratios that matter. Cap rate is NOI divided by the purchase price — the unlevered yield, which lets you compare buildings regardless of how each is financed. As a rough guide, GTA residential rentals often trade around 4.5% to 6%, while some secondary markets reach 6% to 8%. Debt Service Coverage Ratio (DSCR) is NOI divided by the annual mortgage payment; commercial and five-plus unit lenders underwrite to it, usually wanting 1.20 to 1.30, meaning the property earns 20% to 30% more than its mortgage costs.

What affects your cashflow

At today's rates the mortgage payment is almost always the largest line item, so the financing decisions move cashflow more than the rent does. A larger down payment, a longer 30-year amortization, or a lower rate each cut the monthly payment and can flip a property from negative to positive. The operating side matters too: vacancy, property management at roughly 7% to 10% of rent, and a maintenance and CapEx reserve of another 10% or so are real costs even if you self-manage, and leaving them out of the model is the most common way investors talk themselves into a bad deal.

How a lender treats your rent also changes what you can buy. The conservative 50% offset reduces the debt side of your ratios by half the rent; an 80% add-back counts 80% of rent as income; and a 100% offset, offered by a handful of A-lenders and specialty lenders, is the most powerful for scaling a portfolio. (Add-back percentages vary by lender, commonly 50% to 80%.) The right lender policy can swing how much you qualify for on the same file.

A worked example

Consider a $650,000 legal duplex in Hamilton, both units rented for a combined $3,800 a month. With 20% down ($130,000) the mortgage is $520,000, and at an assumed 4.69% (illustrative, not a quote or today’s rate) over a 30-year amortization about $2,680 a month. Now layer in the operating costs: property tax around $450 a month, insurance $130, a 5% vacancy allowance of about $190, management at 8% of effective rent (roughly $289), and a combined maintenance and CapEx reserve of 10% of effective rent (about $361).

Effective monthly rent after vacancy is about $3,610. Operating expenses — tax, insurance, management, and the reserve, but not the mortgage — total roughly $1,264, which leaves an NOI of about $2,382 a month, or $28,580 a year. Cap rate is that $28,580 over the $650,000 price, about 4.4%. Subtract the $2,680 mortgage from the $2,382 NOI and the property runs at roughly negative $344 a month. DSCR is NOI over annual debt service, $28,580 ÷ $32,280, about 0.87 — below the 1.20 a commercial lender would want. This is a common pattern in the Toronto-Hamilton area in 2026: modest cap rate, slightly negative cashflow, with the investor betting on appreciation and principal paydown.

How to improve cashflow

Take that same duplex and the levers become obvious. Putting 25% down instead of 20% drops the mortgage to about $487,500 and the payment to roughly $2,520, cutting the monthly shortfall by about $170. Pushing rent to $4,100 adds about $285 of effective rent, roughly $234 after management and reserves, cutting the monthly shortfall rather than guaranteeing positive cashflow. In Ontario, sitting tenants in units first occupied before 15 November 2018 are subject to the annual guideline (2.1% for 2026); higher rent usually comes at turnover or from adding a legal unit. A rate 50 basis points lower trims the payment by roughly $150 a month. Stacking even two of these — a bit more down and slightly higher rent — moves this file from a $344 monthly bleed to genuine positive cashflow.

Beyond the obvious, the financing structure is where a broker earns their keep. Matching the file to a lender with a favourable rental-offset policy can be the difference between qualifying and not, and a forced-appreciation BRRRR plan lets you refinance at a higher value and pull your down payment back out to buy again. Build the numbers honestly, then optimize the financing around them rather than wishing the rent were higher.

Related scenarios

For five-plus unit buildings the lender underwrites to DSCR rather than your personal income, so model those on our commercial mortgage and DSCR calculator. If you are buying a one-to-four unit rental, our investment property mortgage guide covers the 20% down rule and the rental-offset options in detail. And when you reach the refinance step of a BRRRR, the refinance calculator shows how much capital you can pull out at the new appraised value.