Operating Expense Ratio
Calculator
Results
- Operating expense ratio (%)
- 40.277777
- Net operating income
- 344,000
- Net operating margin (%)
- 59.722222
Property management results
| Operating expense ratio (%) | 40.277777 |
| Net operating income | 344,000 |
| Net operating margin (%) | 59.722222 |
formula-map diagram
- Operating expense ratio (%)
- 40.277777
- Net operating income
- 344,000
- Net operating margin (%)
- 59.722222
Property management relationship
Formula
OER = operating expenses ÷ effective gross income × 100= 40.277777777778
Note
This is a simplified model: it applies the standard property-management definition to the numbers you entered. Rent affordability uses a flat share-of-income rule and ignores credit history, local screening criteria and household size. Proration assumes a plain daily rate; your lease or local law may prescribe a different convention (for example a fixed 30-day month). Security-deposit interest is simple interest at the rate you enter, while many jurisdictions set the rate, the compounding and the payout schedule by statute. Income, expense, reserve and escalation figures are straight-line and assume the amounts you enter hold steady; they ignore taxes, depreciation, financing changes, capital events, inflation and market turnover. Lease buyout compares the contractual penalty with the remaining rent only and is not a reading of your lease. These results are general information, not legal, tax or investment advice: check your lease and local tenancy law and consult a qualified professional before acting.
More in Property management
See all →Frequently asked questions
What is the operating expense ratio (OER) actually measuring?+
OER is total operating expenses divided by effective gross income, expressed as a percentage — it shows what share of collected revenue is consumed by running the property before debt service. A lower OER means more of every rental dollar flows through to net operating income.
What expenses should be excluded from the operating expense ratio?+
Mortgage principal and interest, capital expenditures (roof replacement, major renovations), depreciation, and income taxes are excluded because OER measures operating performance, not financing or capital decisions. Only recurring costs like property management, insurance, utilities, repairs, and property taxes belong in the numerator.
What is a typical operating expense ratio for rental property?+
Most residential properties run between 35% and 50%, while older buildings or those with utilities included in rent can run higher, sometimes 60%+. Commercial properties on triple-net leases can show much lower ratios because tenants pay many operating costs directly rather than through the landlord's expense line.
Why would a very low OER be a red flag rather than good news?+
An unusually low OER can mean the owner is deferring maintenance, under-reporting expenses, or that a major cost like property management is missing from the books entirely. Always check what's actually included before treating a low ratio as a sign of an efficiently run property.
How does OER differ from the expense-to-value or cap rate calculations?+
OER relates expenses to income collected, while a cap rate relates net operating income (income minus expenses) to purchase price or value. They answer different questions — OER tells you how efficiently the property is operated, while cap rate tells you about return relative to what you paid.