What portion of every rent dollar goes to running the property.
The Operating Expense Ratio (OER) is total annual operating expenses divided by effective gross income, expressed as a percentage. It tells you what share of every rent dollar gets consumed by running the property — and is the cleanest measure of operating efficiency at a given asset.
OER is one of the most diagnostic metrics in property analysis. A property with a 35% OER is keeping 65 cents of every rent dollar before debt service — efficient. A property with a 55% OER is keeping 45 cents — much harder to make work. Across otherwise-identical properties, the one with the lower OER is dramatically more valuable because more revenue becomes NOI.
OER varies systematically by asset class. Net-leased commercial properties (NNN retail, industrial) have OERs as low as 5–15% because tenants pay most expenses directly. Class A multifamily runs 30–35% OER. Class B/C multifamily typically runs 40–50% due to higher repair, turnover, and management intensity. Hospitality can run 60–75% OER because hotels are essentially operating businesses sitting on real estate.
A property's OER should be compared to its own class's benchmark, not across classes. A Class C apartment at 38% OER is a star performer; a Class A apartment at 38% OER would have problems. The benchmark always needs to be class-and-market specific to be meaningful.
OER is also the central operating lever in value-add strategies. A 5-point reduction in OER (from 47% to 42%) often translates to a 7–10% increase in NOI, which at a constant cap rate translates to a 7–10% increase in value. Most value-add plays target both top-line rent growth and OER reduction — together they compound into the equity creation that drives the deal.
| Effective Gross Income | $847,000 |
| Operating expenses: | |
| Taxes & insurance | $118,000 |
| Repairs & maintenance | $72,000 |
| Property management (5%) | $42,350 |
| Utilities (common areas) | $28,500 |
| Payroll | $54,000 |
| Marketing, admin, reserves | $26,150 |
| Total operating expenses | $341,000 |
| OER = $341,000 ÷ $847,000 | 40.3% |
Depends on asset class. Class A multifamily 30–35%. Class B 40–47%. NNN commercial 5–15%. Always benchmark against the property's own class.
No — debt service is excluded. OER measures property-level operating efficiency, separate from how the owner chose to finance.
Generally no — capex (roof, HVAC, major systems) is treated below the line. However, "reserves for replacement" (annualized estimate of expected capex) is included by lenders in their OER calculation.
Two ways: increase EGI (raise rents, reduce vacancy) or decrease expenses (challenge property taxes, shop insurance, in-house management, energy efficiency). Most value-add plays attack both.
Yes — even when the owner self-manages, lenders impute a market-rate management fee (usually 4–8% of EGI). Self-managed properties shouldn't pretend management is free.
Matrix underwrites multifamily and commercial loans on trailing OER and stabilized expenses — so the loan that funds is one your property can actually service.
