Understand your operating numbers · Part 1 of 6

Operating expenses: what it costs to keep a rental running

Learn which rental costs belong in operating expenses, what to keep separate, and how to investigate changes using a practical annual CAD example.

Operating expenses are the costs of keeping a rental property running: things such as property taxes, insurance, management, owner-paid utilities, and routine maintenance. Tracking them helps you see whether the property is becoming more expensive to operate, even before you consider its mortgage.

Here we use a property-performance definition, not a tax-return category. We keep financing, major capital spending, and income tax separate. An expense can matter to your bank balance without belonging in this operating total.

Start with three separate buckets

Imagine a rental as a small machine. Operating expenses keep it running. Capital spending replaces or improves important parts. Financing pays for the money used to buy it.

Those buckets answer different questions:

Operations: what does this property cost to run?
Capital work: what larger purchases or projects does it need?
Financing: what must the owner pay the lender?

Keep all three in your records. Separating them makes the explanation clearer; it does not make the other bills disappear.

What belongs in the operating total?

For this series, include recurring property-level costs such as:

Category	What to record
Property taxes	The property's applicable annual charges
Insurance	Coverage relating to the period being measured
Management	Paid management and recurring leasing/administration costs
Owner-paid utilities	Utilities you are responsible for under the rental arrangement
Routine repairs	Work that maintains the property, separately flagged when classification is uncertain
Other recurring costs	Relevant cleaning, grounds care, bookkeeping, or similar costs

This approach supports the NOI calculation. The US Office of the Comptroller of the Currency also separates financing and income taxes from operating performance, although its underwriting convention includes replacement reserves. Our owner-tracking convention shows those reserves separately. OCC commercial real estate handbook.

Exclude mortgage principal and interest from this particular total. Also separate capital purchases, depreciation, personal expenses, and transfers into a reserve account. If a mortgage payment collects property taxes as well as loan payments, split its components rather than recording the whole withdrawal as an operating expense.

Vacancy is a reduction in income in our examples, not an expense added a second time.

A hypothetical annual example

Suppose one rental has these costs, all in CAD:

Expense	Annual amount
Property taxes	4,000
Insurance	1,600
Owner-paid utilities	1,200
Management	2,400
Routine repairs	1,600
Other recurring costs	1,200
Total	12,000

That is an average of CAD 1,000 a month. It does not mean every month costs exactly CAD 1,000: insurance renewals and repairs can arrive in lumps.

The property also pays CAD 18,000 of annual mortgage principal and interest and spends CAD 3,000 on capital work. Those amounts stay outside the CAD 12,000 operating total, but enter the owner's cash-flow calculation.

How much is too much?

There is no useful universal dollar ceiling. A larger building, owner-paid heating, expensive insurance, or more intensive maintenance changes what a reasonable budget looks like.

Start with your property's annual budget and trailing 12 months. Then investigate the category behind a change.

Signal	Question to ask	Possible next step
Utilities rise unexpectedly	Did rates, consumption, occupancy, or a leak change?	Compare bills and meter readings; investigate the cause
Repeated repairs on one component	Are we repairing the same failure repeatedly?	Obtain a condition assessment and compare repair/replacement options
Costs look unusually low	Are bills missing or maintenance postponed?	Reconcile records and inspect upcoming needs
Management charges differ from budget	Is this a new recurring cost or a one-time leasing fee?	Check the agreement and classify it consistently

Suggested cadence: record bills monthly, investigate material surprises promptly, and review the trailing-year pattern quarterly. These are workflow suggestions, not regulatory thresholds. Avoid cutting essential upkeep just to improve a ratio. The property does not know it is being asked to look better in a spreadsheet.

Operating records are not your tax return

For Canadian rentals, the CRA's deduction rules have their own requirements. For example, eligible interest can appear in rental tax expenses even though we exclude it from operating performance. Do not copy your NOI categories straight into a tax return. CRA deductible rental expenses.

Keep the invoice, date, property, category, and an explanation for unusual items. Flag repair-versus-capital questions for separate review.

Sources

OCC, Commercial Real Estate Lending, Version 2.0, glossary “Net operating income,” printed page 140. March 2022 edition with March 2025 revisions; US underwriting context. Accessed October 1, 2026.
CRA, Rental expenses you can deduct, Canadian rental-tax guidance. Accessed October 1, 2026.

Educational content, not financial, tax or legal advice.