Cap rate: what it tells you about a property before financing

Cap rate compares a property's annual net operating income with its price or value. It helps you examine operating income before financing. It does not tell you how much cash your mortgage will leave you, or your total investment return.

The denominator matters: a cap rate based on the purchase price answers a different question from one based on today's estimated value. Label both the income period and the price basis before comparing percentages.

The simple version

Imagine looking at the rental before deciding how to pay for it. How much operating income does the property produce relative to its price? The mortgage comes later. Two buyers can calculate the same cap rate for the same property and still have very different cash flow because they borrow different amounts on different terms.

Define the income and the price

Net operating income, or NOI, is income after property operating expenses. In this series, it excludes mortgage principal and interest, actual capital spending, reserve transfers, depreciation and income tax. See the NOI guide for the full boundary.

Use annual NOI divided by the specified property price or value, then express the result as a percentage.

$$c = \frac{N}{V}\times100\%$$

Here, $c$ is cap rate, $N$ is annual NOI, and $V$ is the stated property price or value. NOI and value use the same currency; value must be positive for this comparison.

For an acquisition comparison, name the agreed purchase price. This article uses the price of the property alone, rather than price plus closing costs and initial work. If you use total acquisition cost, label that different basis. Your down payment is not the property's price.

For a current-value comparison, name the valuation date and evidence. Pairing last year's actual NOI with today's value is a descriptive comparison. Pairing next year's expected NOI with today's value is a forecast. Neither label can be omitted just because the formula looks the same.

The OCC's commercial lending handbook describes direct capitalization as converting stabilized NOI into value using an appropriate cap rate. Its US lending context uses underwriting conventions, including a replacement-reserve allowance, that differ from our owner NOI. A lender's adjusted income should therefore be reconciled before comparing its figure with yours.

A hypothetical CAD example

Our shared operating year has CAD 36,000 of effective gross income and CAD 12,000 of operating expenses. That leaves CAD 24,000 of annual NOI. The purchase price is CAD 500,000.

$$c = \frac{24{,}000}{500{,}000}\times100\% = 4.8\%$$

This means annual NOI equals 4.8% of the acquisition price under our definition. It does not mean you received 4.8% of your invested cash.

Now stipulate an end-of-year value of CAD 520,000, without changing NOI:

$$c = \frac{24{,}000}{520{,}000}\times100\% \approx 4.62\%$$

The current-value ratio is lower because the denominator increased. The property's operating income did not deteriorate. Conversely, a falling valuation could raise this ratio while the owner suffers a value loss. A rising cap rate alone is not proof of improvement.

What the percentage leaves out

Neither calculation includes financing, income tax, annual capital spending or a future sale. In our example, CAD 18,000 of debt service and CAD 3,000 of actual annual capital spending reduce cash after CapEx to CAD 3,000. The cash-on-cash guide compares that cash with the owner's investment.

Compare properties only after checking whether their NOI uses similar vacancy, management, repairs and reserve assumptions. A seller's forecast based on full occupancy is not directly comparable with your trailing-year results. A deferred roof project can matter greatly even when it is outside the chosen NOI definition.

This research establishes no universal healthy cap rate. A meaningful comparison needs relevant property and market evidence, consistent definitions, and an understanding of condition and risk. A higher number can follow a lower price, stronger income, or assumptions that need scrutiny.

Put it to use

Calculate cap rate when reviewing a purchase and at an annual valuation review; update it after a material income or value change. This is a suggested workflow, not a required schedule.

When the ratio changes, split the change into NOI and value. Ask whether collections changed, whether expenses were omitted, and whether the valuation evidence is current. Rebuild the income statement or obtain better comparable evidence before drawing an investment conclusion. For cash tied up today, continue with return on equity.

Sources

• OCC, Commercial Real Estate Lending handbook, version 2.0, March 2022, updated March 20, 2025; printed pp. 42–44 and 140. Direct capitalization and underwriting scope; checked October 1, 2026. Worked numbers and owner NOI are declared teaching assumptions.