CAM billing errors do not fix themselves. The property management software that miscalculated your share this year ran the same formula last year and the year before that. If you found an error on your 2025 reconciliation, the real question is not "how much did I overpay this year?" It is "how many years has this been happening?"
I built CAMAudit because I kept seeing the same pattern in published audit case studies: a single formula error, repeated across every billing cycle, compounding into five-figure and six-figure overcharges that nobody caught. Here are the five signs yours has been doing the same thing.
1. Your CAM Charges Increased Every Year Without a Clear Explanation
A 3% annual increase is normal if your lease includes an escalation clause. But if your CAM went up 8%, 12%, or 15% without a corresponding change in building expenses, something structural is wrong, and it is probably not new.
Common causes: the landlord applied an escalation to an already-inflated base, or a capital expenditure that should have been amortized got folded into operating expenses in a prior year and has been rolling forward ever since.
2. Your Pro-Rata Share Percentage Changed Without a Building Size Change
Your pro-rata share is your square footage divided by the building's total leasable area. If that percentage changed between billing periods but the building did not add or remove space, the denominator is wrong, and it is probably wrong in every period.
A pro-rata share error is one of the most expensive repeating errors because it affects every single line item on the reconciliation. A 0.5% denominator error on a $500,000 CAM pool is $2,500 per year. Over five years, that is $12,500 from one input being wrong.
3. Management Fees Exceed Your Lease Cap
If your lease caps the management fee at 5% of operating expenses and the landlord bills 5% of gross revenue instead, the gap grows every year as revenue changes. This is not a rounding error. It is a configuration setting in the billing system that nobody rechecked after the lease was signed.
According to industry data, management fee overcharges appear in 15 to 25% of NNN leases reviewed. When they appear, they appear in every billing period.
4. Your Base Year Numbers Look Unusually Low
The base year sets the floor for what you pay. If your base year expenses were understated (too low), every escalation charge above that base is inflated. A $10,000 understatement in the base year produces $53,091 in cumulative overcharges over five years at 3% escalation.
Check whether your base year reconciliation matches the actual expenses for that period. If you cannot verify it, that is the sign.
5. You Have Never Audited Before
If you have been in your space for three or more years and have never reviewed a reconciliation against your lease provisions, the probability of a compounding error is high. Tango Analytics (2023) found material errors in 40% of CAM reconciliations. The probability that zero errors exist across multiple years of your lease is low.
The good news: most states give you a 3 to 10 year lookback window through the statute of limitations on written contracts. You can recover past overcharges, not just this year's.
What to Do Next
Upload your lease and CAM reconciliation statement. CAMAudit runs 20 forensic detection rules, including management fee caps, pro-rata share calculations, gross-up methodology, and CAM cap violations. If it finds an error this year, upload prior years too. The same error is almost certainly there.
The 5-audit credit pack covers five years of the same lease. That is the most common way tenants use CAMAudit for multi-year recovery.