Base years use actual first-year costs as the benchmark but are vulnerable to manipulation. Expense stops use a fixed negotiated amount that is harder to game.
A base year provision sets a specific calendar year (usually the first year of the lease) as the benchmark for operating expenses. The tenant pays their proportionate share only of expenses that exceed the base year amount. If expenses are lower than the base year, the tenant pays nothing above base rent.
An expense stop is a fixed dollar-per-square-foot threshold negotiated at lease signing. The landlord covers all operating expenses up to the stop amount, and the tenant pays their share of any expenses above that threshold. Unlike a base year, the stop is a negotiated number, not tied to actual expenses in any specific year.
| Dimension | Base Year | Expense Stop |
|---|---|---|
| How the threshold is set | Based on actual expenses in a specific year | Negotiated dollar amount at signing |
| Manipulation risk | Higher, landlord can suppress base year costs | Lower, amount is fixed in the lease |
| First-year exposure | Typically zero, since expenses match the base year | Depends on whether stop exceeds actual expenses |
| Gross-up complexity | Base year often needs gross-up adjustment | Stop amount is a fixed number, no gross-up needed |
| Common lease types | Office, multi-tenant buildings | Office, some retail |
Base year manipulation is a well-known landlord tactic: by keeping expenses artificially low during the base year (deferring maintenance, negotiating one-time vendor discounts), the landlord ensures that every subsequent year produces higher pass-throughs. Expense stops remove this manipulation vector but require careful negotiation to set the right threshold.
Base year provisions carry more manipulation risk because the landlord controls the spending that sets the benchmark. A suppressed base year can cost tenants thousands annually for the entire lease term. Expense stops are more transparent, but a poorly negotiated stop that is set below actual market expenses will cost the tenant from day one.
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Find My OverchargesThis page provides general educational information. It is not legal advice and may not reflect the most current law in your state. Consult a licensed attorney for advice specific to your situation.
