CAM Reconciliation: How It Works + Free Calculator

What is CAM reconciliation?

CAM reconciliation is the year-end process where a commercial landlord compares the common area maintenance (CAM) estimates tenants paid during the year with what the property actually spent. Each tenant then pays the difference, or receives a credit if they overpaid.

During the year, tenants pay a fixed monthly CAM estimate along with base rent. After December 31, the landlord totals the real costs, applies each tenant's lease terms, and sends a reconciliation statement showing the final numbers.

CAM reconciliation applies to NNN (triple net), double net and modified gross leases, where tenants share operating costs. It doesn't apply to full-service gross leases, where the landlord absorbs those costs.

What counts as CAM?

CAM covers the costs of running and maintaining shared areas of a property. Common examples include:

• Landscaping and snow removal
• Parking lot sweeping, striping and lighting
• Janitorial service for shared areas
• Security
• Common area utilities
• Repairs and routine maintenance
• Property management fees

Property taxes and insurance are often billed alongside CAM as part of NNN charges. Your lease decides what's included, what's excluded and how each category is shared. Always reconcile against the lease, not a general rule.

How CAM reconciliation works, step by step

1. Total the year's actual expenses by category.
2. Remove excluded categories the tenant's lease doesn't allow.
3. Gross up variable expenses if the lease allows it and occupancy was below the target.
4. Apply the tenant's pro-rata share to the expense pool.
5. Apply any cap on controllable expenses.
6. Add the admin or management fee, if the lease allows one.
7. Subtract a base year or expense stop, if the lease has one.
8. Prorate for partial-year occupancy if the tenant moved in or out mid-year.
9. Subtract the estimates already paid. A positive result is a balance due. A negative result is a credit.

The calculator above follows this exact order and shows every step.

How to calculate pro-rata share

A tenant's pro-rata share is their leased area divided by the property's total area:

Pro-rata share = tenant's leased sq ft ÷ total sq ft

Example: a 4,000 sq ft tenant in a 50,000 sq ft shopping center has an 8% share. If the center's recoverable CAM expenses were $250,000, the tenant's share is $20,000. If the tenant paid $1,500 a month in estimates ($18,000 for the year), they owe $2,000.

Check which total your lease uses. Most use the property's gross leasable area (GLA). Some use only the occupied area, which gives each tenant a larger share when space is vacant.

Try it in the calculator above

What is a gross-up?

A gross-up adjusts variable expenses to what they would have been at a set occupancy level, often 90% or 95%. It applies only to costs that rise and fall with occupancy, such as janitorial service or utilities.

Without a gross-up, a landlord with vacant space can't recover the full cost of running the property, because each tenant's share is based on total area while the costs reflect fewer occupants. Fixed costs like property taxes and insurance should never be grossed up.

Try it in the calculator above

CAM caps: non-cumulative, cumulative compounded and cumulative simple

Many leases limit how much a tenant's controllable expenses can rise each year, often 3% to 5%. Uncontrollable costs like taxes, insurance and snow removal are usually left uncapped. How the cap is measured makes a real difference.

Example: a tenant's controllable share was $8,000 in the base year, with a 5% cap.

• Non-cumulative (year over year): each year's limit is last year's actual amount plus 5%. Unused room is lost.
• Cumulative, compounded: the limit grows 5% a year from the base year, compounding. After 2 years, the limit is $8,820. Unused room carries forward.
• Cumulative, simple: the limit grows by 5% of the base amount each year, without compounding. After 2 years, the limit is $8,800.

Read the cap clause carefully. The method is often stated in a single sentence.

Try it in the calculator above

Admin fees, base years and expense stops

Admin or management fees let the landlord charge a percentage on top of CAM, often 10% to 15%. Leases differ on whether the fee is calculated before or after the cap is applied, so check the wording.

Base years appear in office and modified gross leases. The tenant pays only the increase in expenses above a chosen base year, not the full amount.

Expense stops work the same way but use a fixed dollar amount, often stated per square foot. For example, an $8.50 per sq ft stop on a 4,000 sq ft tenant means the tenant pays only expenses above $34,000.

When is the CAM reconciliation due?

Most leases require the landlord to deliver the reconciliation statement within a set window after year-end, commonly 30 to 90 days. Some leases say a landlord who misses the deadline loses the right to collect the shortfall, so check your lease's exact wording.

Tenants usually have a defined period after receiving the statement to review the landlord's records and dispute charges. A clear, well-documented statement reduces disputes.

How to send a reconciliation tenants won't fight

Tenants push back most on vague line items, unexplained admin fees and repairs that look like capital improvements. To keep things smooth:

• Break expenses into clear categories, not one lump sum.
• Show the pro-rata share math and the total area used.
• Show any gross-up, cap and admin fee as separate lines.
• Keep invoices and receipts ready in case the tenant asks to review them.
• Send a short cover letter with the balance due or credit and the payment deadline.