THE SHORT ANSWER

The 1% rule is an informal screening shortcut that compares a property's monthly gross rent with 1% of its price or stated acquisition basis. It is not a lending rule, appraisal method, or proof of positive cash flow. The expenses and financing it leaves out can change the decision entirely.

How the shortcut is calculated

A simple version divides monthly gross rent by purchase price. If a hypothetical property costs $300,000 and has $3,000 in scheduled monthly rent, the ratio is 1%. Some people include initial repairs in the cost basis; others do not. Specify which version you are using.

Scheduled gross rent is income before vacancy, uncollected rent, taxes, insurance, management, maintenance, reserves, and debt service. Comparing that figure with price is a quick observation, not a forecast of cash remaining.

A property can pass and still have negative cash flow

Continue the hypothetical $300,000 example. Suppose the property's $3,000 scheduled monthly rent falls to $2,700 after vacancy and collection losses. Recurring operating expenses of $1,200 leave $1,500 NOI per month.

If monthly loan payments are $1,400 and reserve funding is $250, the modeled monthly cash flow is negative $150 before income taxes and other costs. The initial rent-to-price ratio still equals 1%. This example demonstrates the shortcut's limitation; it is not a description of a real property.

Why it is particularly weak for 5–50-unit apartments

Buildings can have different utility responsibilities, maintenance needs, property-tax assessments, insurance costs, and staffing arrangements. The same rent-to-price ratio can therefore produce very different NOI.

Commercial lease structures add another complication. Two properties may collect similar base rent while assigning different expenses to tenants. A gross-rent shortcut does not capture those contractual differences.

A property that misses a rough screen is not automatically a good or bad deal. Nor does a high gross yield compensate for unverified legal units, physical defects, or a financing plan that cannot close.

Replace the shortcut with a short analysis

Use the rent-to-price ratio only as a clearly labeled preliminary filter, if you use it at all. Before an investment decision, build effective income, operating expenses, NOI, debt service, reserves, and the full cash requirement.

  • Verify rents and legal unit count.
  • Estimate vacancy and collection losses.
  • Itemize operating costs and capital needs.
  • Use actual proposed debt terms.
  • Test lower income and higher costs before interpreting returns.

Common questions

Does the 1% rule guarantee cash flow?

No. It omits costs and financing. The worked example above meets the shortcut and still shows negative modeled cash flow.

Is the 1% rule the same as cap rate?

No. The shortcut compares monthly gross rent with price. Cap rate compares annual NOI after operating expenses with price or value.

Sources & further reading

Educational content from Real Estate 101. Updated 2026-09-05. Refer to the original sources and your professional advisers for transaction-specific requirements.