Cost Allocation by Square Footage Calculator

About this calculator

Allocating a shared cost by square footage divides the total expense in proportion to each unit's share of the total area — a unit's cost equals the total cost multiplied by that unit's area divided by the total area — on the reasoning that space occupied is a fair, objective proxy for how much of a shared resource a tenant or owner benefits from, whether that's heating, common-area maintenance, property tax, or shared utilities.

Property managers, condo and HOA boards, and commercial landlords use area-based allocation to split costs like CAM (common area maintenance) charges, master-metered utilities, or shared roof and structural repairs across multiple tenants or unit owners fairly, since it avoids disputes that come from splitting costs evenly regardless of unit size — a 2,000 sq ft unit pays proportionally more than a 500 sq ft unit for the same shared expense.

This calculator takes the total cost, a specific unit's square footage and the total square footage of all units, and returns that unit's allocated share of the cost.