The direct answer
CAM charges are common-area maintenance expenses allocated to tenants under many commercial leases. The lease determines which costs are recoverable, how they are allocated, whether caps or exclusions apply and how annual estimates are reconciled with actual expenses.
Identify recoverable expense categories
CAM can include items such as common-area cleaning, landscaping, security, management or repairs, but leases differ substantially. Taxes and insurance may be separate from CAM even when all are billed as additional rent.
To apply the approach to an editable scenario, use the NNN Lease Calculator. For the neighboring question, explore Commercial Rent Calculator.
Check the allocation method
Charges may be allocated by rentable area, occupancy or another contractual method. Gross-up provisions can adjust certain variable expenses when a property is not fully occupied.
Model estimates and reconciliations
Tenants often pay monthly estimates followed by year-end reconciliation. A cash-flow model should distinguish current estimates from actual recoverable costs when the information is available.
Worked example
If recoverable CAM is $300,000 and a tenant’s contractual pro-rata share is 10%, the tenant’s share would be $30,000 before applying any lease-specific caps, exclusions or adjustments.
Common mistakes and limitations
Do not apply one generic CAM definition across leases; recoverability is contract-specific.
Actual NNN leases define recoverable expenses, audit rights, caps and reconciliations contractually.
Frequently asked questions
Are property taxes always included in CAM?
Not necessarily. Many leases bill taxes separately, while others define recoveries differently.
Can CAM charges change each year?
Yes. Actual expenses, occupancy and lease provisions can change the amount.
Sources and further reading
The article’s examples are illustrative arithmetic. The references below provide context for operating, valuation or transaction concepts; they do not endorse the assumptions or the calculator.
- Office of the Comptroller of the Currency — Comptroller's Handbook — Commercial Real Estate LendingNOI, direct capitalization, cap-rate valuation and DCF concepts for commercial real estate.
Read our editorial policy for the scope of these educational methods.