Vacancy Rate Impact Calculator

The Vacancy Rate Impact Calculator quantifies how much income you lose to unoccupied units and helps you plan for realistic cash flow projections. The calculation begins with your gross potential rental income. This is the maximum revenue your property would generate if every unit were occupied and paying rent for the entire year. It is computed by multiplying your monthly rent per unit by the number of units and then by 12 months. Next, the calculator applies your vacancy rate to determine income lost to vacancy. The vacancy rate represents the percentage of time your units are expected to sit empty over the course of a year. For example, an 8% vacancy rate on a single unit renting at $2,000 per month means you lose $1,920 annually to vacancy, which is roughly equivalent to one month of lost rent. Your effective gross income is the gross potential income minus the vacancy loss. This is the figure you should use when projecting cash flow, calculating cap rates, and evaluating whether a rental property meets your return targets. The calculator also shows the impact on a per-unit and per-month basis, making it easy to see how each percentage point of vacancy translates to dollars lost. This is especially useful when comparing markets or properties with different vacancy characteristics. For multi-unit properties, the vacancy impact scales with the number of units but also diversifies your risk. A four-unit property with one vacant unit still generates income from three, whereas a single-family rental produces zero income during vacancy. The calculator helps you visualize this dynamic across different portfolio sizes.