AbraCalc

OER: $250,000 Expenses on $500,000 Gross Income

A property with $250,000 in operating expenses and $500,000 in gross operating income has an OER of exactly 50%.

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How to use this tool

  1. Enter annual operating expenses (excluding mortgage, capex, and income tax).
  2. Enter annual gross operating income (effective rent plus other income).
  3. Read the operating expense ratio.
  4. Check the resulting NOI and NOI margin.
  5. Benchmark the OER against comparable properties — 35-45% is typical for residential.

Larger apartment complexes often benchmark their OER against the 50% rule; this scenario confirms exactly where that threshold lands.

Frequently asked questions

What is a good operating expense ratio?
For residential rentals, an OER in the 35-45% range is common. Lower can mean a more efficient property — or that expenses such as management and reserves have been understated. Compare against similar properties.
What is excluded from the OER?
The mortgage payment, income taxes, depreciation, and capital expenditures are all excluded, matching the definition of net operating income. Only recurring operating costs belong in the numerator.
How does OER relate to NOI margin?
They are complements: OER + NOI margin = 100%. A 40% OER implies a 60% NOI margin. Tracking one automatically tells you the other.