Free Cumulative CAM Cap Bank Calculator

A cumulative CAM cap bank is the running balance of unused cap capacity that carries forward from year to year under a cumulative cap structure. When actual CAM expenses in a given year come in below the cumulative ceiling, the unused allowance does not disappear. It accumulates in the bank. In future years when expenses spike, the landlord can draw on this banked capacity to recover charges above what a simple annual percentage would allow.

The cumulative cap ceiling for any given year equals the base year CAM amount multiplied by (1 + cap percentage) raised to the power of the number of years since the base year. For example, with a $200,000 base year and a 4% cumulative cap, the year 5 ceiling is $200,000 × 1.04^5 = $243,331. The tenant pays the lesser of actual expenses or this ceiling. The bank balance is the ceiling minus what was actually billed in each prior year.

Under most lease drafting, the cumulative cap bank does not reset. The banked capacity compounds throughout the lease term. However, some leases include a reset provision that zeroes the bank at lease renewal or at specific intervals. Review your lease language carefully. The calculator includes a toggle for both scenarios so you can model the lease as written.

A non-cumulative cap limits the year-over-year increase to a fixed percentage of the prior year's actual charges. It does not carry unused capacity forward. If expenses rise by only 1% in a year with a 5% non-cumulative cap, the remaining 4% is lost. Under a cumulative cap, that 4% banks and is available in future years. Over a 5 to 10 year lease, the difference between structures can amount to significant recoverable dollars for the landlord.