California's Commercial Tenant Protection Act: How the 90-Day Notice Mandate Works for Small Businesses

For a small business operating on thin margins, a sudden 20% rent increase delivered with only 30 days' notice is often a death sentence. Whether it is a corner coffee shop in San Diego or a family-owned bookstore in Los Angeles, commercial tenants have historically operated without the safety nets afforded to residential renters. That dynamic has permanently shifted in California. Under the Commercial Tenant Protection Act, known legislatively as SB 1103, qualifying small businesses now have a legal shield against abrupt financial shocks.[1][2]

The legislation, which took effect on January 1, 2025, fundamentally rewrites the rules of engagement between commercial landlords and their smallest tenants. It establishes a first-in-the-nation framework that extends consumer-style protections to the commercial real estate sector. For business owners, the most immediate and tangible change is the end of the 30-day rent shock for significant increases.[2][4]

Under the law, if a landlord intends to raise a qualified tenant's rent by more than 10%—calculated cumulatively over a rolling 12-month period—they are legally required to provide at least 90 days of written notice. For increases of 10% or less, the standard 30-day notice still applies. This extended runway is designed to give mom-and-pop operators the crucial time needed to adjust their pricing models, renegotiate lease terms, or, if necessary, find a new location without the looming threat of an immediate commercial eviction.[1][2]

However, these protections are not universally applied across the commercial landscape. The law specifically targets "Qualified Commercial Tenants" (QCTs), creating a distinct protected class based on size and resources. To qualify, a business must fall into one of three categories: a microenterprise with five or fewer employees, a restaurant with fewer than 10 employees, or a nonprofit organization with fewer than 20 employees.[1][2]

Crucially, the protections are not automatic. To activate their rights under SB 1103, a tenant must proactively provide their landlord with a written self-attestation confirming their status as a QCT. This notice must be delivered before or at the execution of a new lease, and annually thereafter. Without this written declaration, a small business remains subject to the standard, less protective commercial leasing rules.[1][4]

Beyond rent increases, the legislation tackles another historical pain point for small businesses: the opaque world of Common Area Maintenance (CAM) fees and building operating costs. For decades, tenants have frequently faced sudden, unexplained bills for property upkeep, with little visibility into how those costs were calculated or whether they were distributed fairly among the building's occupants.[2]

SB 1103 mandates a new era of transparency for these pass-through expenses. Landlords are now prohibited from charging a QCT for building operating costs unless those costs are allocated proportionately and supported by clear documentation. Furthermore, landlords can only bill for expenses incurred within the previous 18 months or reasonably expected within the next 12 months. If a tenant requests it in writing, the property owner must provide itemized documentation and a signed attestation within 30 days.[1][2]

The law also addresses language barriers that have historically placed immigrant business owners at a disadvantage during lease negotiations. If a commercial lease is negotiated primarily in Spanish, Chinese, Tagalog, Vietnamese, or Korean, the landlord is now legally required to provide a translated copy of the contract in that language prior to execution. This ensures that all key terms are fully understood before any binding signatures are applied.[1][2]

Enforcement of these new rules carries significant weight. If a landlord fails to comply with the operating-cost transparency provisions, a tenant can use that violation as an affirmative defense in an unlawful detainer (eviction) action. In cases where a landlord is found to have acted willfully or with malice, they could be liable for treble and punitive damages, alongside the tenant's attorney's fees.[2][3]

For California's commercial real estate market, the transition has required landlords to overhaul their administrative processes and compliance tracking. Property owners must now carefully monitor the cumulative percentage of rent increases over a rolling year and maintain meticulous records of all building expenses. While the adjustment period has introduced new administrative burdens for property managers, for the state's smallest enterprises, the law provides a much-needed foundation of stability in an otherwise volatile market.[2][4]