CAM stands for Common Area Maintenance, which is a fee paid by tenants to landlords to help cover costs associated with overhead and operating expenses for common areas in commercial real estate. Common areas are spaces used for or benefited by all tenants and include hallways, elevators, parking lots, lobbies, public bathrooms, and building security. CAM charges are usually paid monthly in addition to rent and can increase over the term of the lease. The amount paid is a pro-rata amount based on the tenants square footage versus the project or building as a whole. CAM charges can be either fixed or variable.

CAM expenses are an estimate and are often reconciled at year-end. The property manager will provide tenants with a statement of the actual CAM and Operating Costs for the previous year. This statement will state the amount in which the tenant has underpaid or overpaid, and they will either receive credit back or owe the balance. CAM charges generally include property management fees, and depending on the property type, it can include hallways, lobbies, restrooms, parking lots, exterior lighting, trash removal, insurance, etc. .

It is important to know about CAM expenses because they can be difficult to predict and can increase significantly from year to year, which can be especially problematic for tenants who are on a tight budget and cannot afford to pay for unexpected increases in CAM fees. In some cases, CAM fees are tied directly to operating costs, which can be difficult to predict. Furthermore, CAM fees may also have price floors in order to prevent landlords from passing on their overhead as disguised CAM charges.