The direct answer
Physical occupancy measures occupied units or space, economic occupancy measures collected or collectible revenue relative to potential revenue, and collection loss captures billed or expected rent that is not collected. They can move differently when rents, concessions or delinquency vary.
Physical occupancy counts use, not dollars
A property with 90 occupied units out of 100 is 90% physically occupied for that snapshot. The measure does not show whether all units have the same rent, whether tenants paid, or whether concessions reduced revenue. Average annual occupancy also differs from a single-date count.
To apply the approach to an editable scenario, use the Vacancy Rate Calculator. For the neighboring question, explore Rental Property Cash Flow Calculator.
Economic occupancy follows revenue
Economic occupancy compares actual or effective rental revenue with a defined potential-rent base. A fully occupied property can have weaker economic occupancy because of concessions, below-market leases or nonpayment. State the denominator and whether the measure uses billed or collected revenue.
Keep collection loss visible
Bad debt or delinquency can be hidden if an analysis treats an occupied unit as fully productive. Reconcile rent roll charges with receipts and concessions. For underwriting, model the revenue effect rather than assuming a physical vacancy percentage captures every source of lost rent.
Worked example
A 100-unit property with 95 occupied units is 95% physically occupied. If gross potential rent is $120,000 for the period but effective collected rent is $108,000 after concessions and nonpayment, economic occupancy on that defined base is 90%.
Common mistakes and limitations
Do not multiply physical occupancy by asking rent and assume the result equals collected revenue. Rent mix, concessions and delinquency can create a meaningful gap.
Physical vacancy and economic vacancy are different concepts; label the selected method clearly.
Frequently asked questions
Can a property be physically full but economically weak?
Yes. Concessions, below-market leases or nonpayment can reduce revenue even with high physical occupancy.
Is collection loss the same as vacancy?
No. Vacancy reflects unoccupied space; collection loss reflects revenue not received from amounts otherwise due or expected.
Sources and further reading
The article’s examples are illustrative arithmetic. The references below provide context for operating, valuation or transaction concepts; they do not endorse the assumptions or the calculator.
- IRS — Publication 527 (2025), Residential Rental PropertyRental income and expense concepts; operating/rental expense context.
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