What is CAM (common area maintenance)?

Q: What does CAM include?

The costs of operating shared areas such as parking, landscaping, lighting, security, common-area utilities, and often management fees, reimbursed by tenants in net leases.

Q: Can CAM be negotiated?

Yes. Tenants commonly negotiate caps on controllable increases, exclusions for capital costs, and audit rights.

Last updated: August 2026

The short answer

CAM — common area maintenance — is the tenant’s share of the cost to operate and maintain a property’s shared areas: parking lots, landscaping, lighting, sidewalks, security, and common-area utilities. In net leases, tenants reimburse CAM on top of base rent, usually pro-rata by their share of the building’s square footage.

What CAM typically covers

Parking lot upkeep, striping, and snow removal
Landscaping and exterior lighting
Common-area cleaning, security, and shared utilities
Property management fees (often)
Sometimes property taxes and insurance, depending on how the lease defines the “nets”

How CAM is charged

A tenant pays their pro-rata share — their leased square footage divided by the building’s total leasable area. The landlord estimates annual CAM, bills it monthly, and then runs a year-end reconciliation (a “true-up”) to square the estimate against actual costs.

Pro-rata example

Total building leasable area	50,000 sf
Your suite	5,000 sf
Your pro-rata share	10%
Annual building CAM	$200,000
Your annual CAM ( 10% of $200,000 )	$20,000

Where CAM gets negotiated

CAM is one of the most negotiated — and most audited — line items in a lease:

Caps. Tenants negotiate annual limits on increases in “controllable” CAM (landscaping, management), while “uncontrollable” items (taxes, insurance, snow) often stay uncapped.
Exclusions. Capital expenditures, roof and structure, and leasing costs are commonly excluded from CAM.
Audit rights. Tenants often reserve the right to audit the landlord’s CAM reconciliation.

Why it matters

CAM is exactly what turns a “cheap” NNN base rent into a real occupancy cost. For an agent, understanding CAM is how you compare deals honestly and advise a client on their true all-in cost per square foot.

Common questions

What does CAM include?

The costs of operating shared areas — parking, landscaping, lighting, security, common-area utilities, and often management fees — that tenants reimburse in net leases.

How is CAM calculated?

By pro-rata share: your square footage divided by the building’s total leasable area, applied to annual CAM costs. It’s estimated monthly and reconciled at year-end.

Can CAM be negotiated?

Yes — tenants commonly negotiate caps on controllable increases, exclusions for capital costs, and the right to audit the landlord’s reconciliation.