If you own multifamily property across the Westside and South Bay, you already know that crossing a city line can mean crossing into a completely different set of rules. A building in Santa Monica answers to one rent control board. A property five miles away in Inglewood answers to another. And a parcel in an unincorporated pocket like Westmont or Del Aire falls under yet a third set of regulations, run by the county instead of any city at all.

Mixing these up isn't a small mistake. Getting the wrong ordinance applied to your property can lead to real penalties: fines, forced rent refunds to tenants, or an eviction that gets thrown out because a step was skipped.

Below is a plain-language look at how Santa Monica, Inglewood, and unincorporated L.A. County each handle rent control, so you know exactly which rules apply to your building.

Santa Monica: The Strictest Rules on the List

Santa Monica has had rent control since the 1970s, and it's still one of the toughest ordinances in the country. An elected Rent Control Board oversees it directly.

• Which properties it covers: Most multifamily buildings built before April 10, 1979.
• How much you can raise rent: The board sets a General Adjustment each year, equal to 75% of the local Consumer Price Index, and then caps it at a flat dollar amount. For 2026, that works out to a 2.6% increase with a hard monthly ceiling on top.
• Where owners get tripped up: You cannot pass the cost of a capital improvement on to tenants without board approval first. And if you miss the annual registration deadline or send a notice incorrectly, the city can freeze your right to raise rent at all that year.

Inglewood: Rules That Shift Based on Building Size

Inglewood's Housing Protection Ordinance splits owners into two groups. Smaller buildings get more breathing room, while larger complexes face tighter limits.

• Which properties it covers: Residential buildings built before December 2004, or anything older than 15 years under the state's rolling backstop.
• How much you can raise rent: Buildings with 5 or more units are capped at local CPI or 3%, whichever is higher. Buildings with 4 units or fewer get CPI plus 5%, up to a 10% total cap.
• Where owners get tripped up: Every covered unit has to be registered with the city's Housing Protection Department. Raise the rent on an unregistered unit and it's a violation, even if the percentage itself is legal.

Unincorporated L.A. County: The One People Miss

A lot of owners assume that any address listed as "Los Angeles" falls under the city's rules. That's not always true. Neighborhoods near Hawthorne, West Athens, and Lennox actually sit in unincorporated county territory, governed by the County's Rent Stabilization and Tenant Protections Ordinance.

• Which properties it covers: Multifamily buildings with a residential occupancy permit issued on or before February 1, 1995.
• How much you can raise rent: The county bases its cap directly on regional CPI, with a small adjustment for owners who hold 10 or fewer units countywide. Recent increases have generally landed under 3%.
• Where owners get tripped up: Relocation assistance rules for no-fault evictions are detailed and specific, and there are strict limits on passing through utility costs or capital improvements to tenants.

Side-by-Side Comparison

The short version: know which jurisdiction your property actually sits in before you set next year's rent roll. A five-minute drive can put you under a completely different set of rules, and the penalty for guessing wrong falls on the owner, not the city.