NNN vs. CAM: One Is a Lease Type, the Other Is a Line Item

"NNN" and "CAM" get used as if they were the same charge, including by people who negotiate commercial leases for a living. They are not. One describes the structure of a lease — which side carries the operating costs. The other is one expense category inside that structure. Reading a quoted rate as though the two were interchangeable is how a space that looked affordable turns out not to be.

This is an observational explainer of the two terms and how they relate. It is general information, not advice about your documents. The legal judgment about what to do with what you find is yours.

The short version

NNN is a lease type. It says the tenant pays base rent plusthree categories of operating cost, traditionally property taxes, building insurance, and maintenance. Those three categories are the "nets."

CAM— common area maintenance — is the third of those nets. It is the maintenance bucket: the shared costs of running the property that no single tenant consumes alone.

So CAM sits inside NNN. Every triple net lease has a CAM component. Not every charge labeled CAM appears in a triple net lease, because gross and modified-gross leases can pass through a CAM charge without adopting the full net structure. The relationship runs one way, which is why the two words are not swappable even though the documents often use them loosely.

Why the confusion is built into the listings

A listing quoting "$32/SF NNN" is quoting base rent only. The three nets are additional, and the listing rarely says how much they run. A listing quoting "$32/SF plus CAM" is doing something different: naming one net and leaving the treatment of taxes and insurance unstated. The two quotes can describe leases with very different total occupancy costs, and neither number is the number that gets paid.

The gap between quoted rate and total cost is set by the lease, not the listing. Our NNN charges explainer covers what typically sits in each of the three buckets.

Why CAM is the contested one

Of the three nets, taxes and insurance are largely third-party bills. A tax assessment arrives from the county; an insurance premium arrives from a carrier. The landlord passes them through, and while the allocation can be argued, the underlying number was set by someone with no stake in the lease.

CAM is different. It is landlord-directed spending — who gets hired, what gets replaced, how often the lot is resurfaced, whether the management fee is a percentage of everything else. The number is produced by the party billing it. That structural difference, not the dollar amount, is what makes CAM the category where reconciliation disputes concentrate. The year-end true-up mechanics are covered in our CAM reconciliation walkthrough.

The terms that decide what each one covers

• The CAM definition itself. Usually an inclusive list followed by a catch-all. The catch-all does most of the work. Whether capital expenditures, roof and structure, or the landlord's own overhead fall inside it is set here, not by convention.
• Administrative or management fees. Commonly a percentage added on top of CAM. Whether that percentage is calculated on CAM alone or on CAM plus taxes and insurance changes the total, and the two drafts read almost identically.
• Gross-up provisions. These restate variable costs as if the building were substantially occupied. In a partly vacant property the effect is that a tenant pays a share of costs the building did not actually incur.
• Pro-rata share. The denominator matters as much as the numerator. Whether the share is measured against leased space or leasable space determines who absorbs vacancy.
• Caps. Negotiated versions commonly cap the controllable portion of CAM — often on a cumulative or compounding basis — while leaving taxes and insurance uncapped. A cap that covers all three nets and one that covers only controllable CAM are very different protections.
• Audit rights. The provision that determines whether any of the above can be tested. Its value depends on the notice window, who bears the cost, and whether an error triggers a refund.

Reading the two side by side

A useful way to hold the distinction: NNN answers "what kind of lease is this?" and CAM answers "what is in the maintenance bill?" A lease can be triple net with a tightly defined, capped, auditable CAM clause, or triple net with an open-ended one, and the label is identical in both cases. The structure is visible from the lease type; the exposure is not. Leases where the CAM definition is open-ended and uncapped are commonly reviewed by counsel before signature. What you do with that information is your call.

Related: commercial lease analysis · CAM reconciliation, line by line · NNN charges: who pays what · single vs. double vs. triple net · NNN vs. gross lease.