SB 346 Just Gave Cities a New Way to Catch Unregistered Airbnbs

If you have been treating your registration status as something you will get around to eventually, this is the year that catches up with you. California's SB 346 took effect on January 1, 2026, and it lets cities request host data directly from Airbnb, Vrbo, and other booking platforms. San Francisco has already started using it. This is not a small procedural update, it is a real shift in how easy it is for a city to find a listing that never registered.

What SB 346 Actually Does

SB 346 is what is called an enabling law. It does not automatically apply everywhere, a city or county has to pass its own ordinance to activate it. But once that happens, platforms are required to hand over host name, property address, nights booked per year, and registration status within 15 days of a qualifying request. Platforms are also barred from telling you a request was made about your listing. If a platform refuses to comply, it can face fines up to 10,000 dollars a day, so there is real pressure on Airbnb and Vrbo to cooperate quickly.

Why San Francisco Hosts Should Pay Close Attention

San Francisco has already invoked SB 346 and is using the data to identify and remove listings that are not properly registered. The city only has somewhere around 1,800 to 2,200 registered hosts, so it is a tight market and a closely watched one. San Francisco also caps unhosted rentals at 90 nights a year and generally allows only one listing per multi unit building. If your registration number is not correctly listed and your numbers do not line up with what the city expects, this is the mechanism that surfaces it now instead of quietly slipping by.

Seattle Hosts Are Not in the Clear Either

Seattle does not fall under SB 346, that is a California law. But the direction is the same everywhere. Seattle already requires a short term rental license, caps most operators at two units with one as a primary residence, and layers on its own lodging tax rules. Cities across the country are moving toward more data sharing between platforms and local government, not less. If your license number, your unit count, or your tax filings have any gaps, now is a good time to close them before your city builds its own version of what San Francisco just did.

A Quick Checklist Worth Running Today

• Confirm you actually have a current registration or license number on file, not just an application you started

• Make sure that number is listed correctly on every platform, not just the one you check most often

• Track your unhosted nights closely if your city has an annual cap

• Keep your transient occupancy tax or lodging tax filings current, even in slow months

• Do not assume quiet means compliant, assume the opposite until you have actually checked

None of this is about scaring anyone out of hosting. It is about making sure the paperwork side of your business keeps pace with how fast the rules are changing this year. We build compliance checks into how we manage properties for owners across the Bay Area and Seattle, so nothing sits exposed while you are busy running the rest of your life. If you want a second set of eyes on what is live on your account right now, you can book a co hosting consultation with us here and we will walk through it with you.