What are CAM charges and how do NNN leases work?
A triple net (NNN) lease means you pay base rent plus your proportional share of the building's operating costs — property taxes, insurance, and common area maintenance, known as CAM charges.
CAM covers the upkeep of shared spaces like lobbies, hallways, parking, and restrooms. Because these charges are added on top of base rent, the advertised rate never reflects your true occupancy cost. Each year, the landlord reconciles estimated CAM payments against actual expenses, which can result in an additional bill or a credit. Tenants should always ask for a history of operating expenses, confirm the right to audit the reconciliation, and negotiate a cap on annual increases. Understanding CAM before signing prevents the most common cost surprise in commercial leasing.
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