The law requires residents to sign up with the planning department and prove they have liability insurance.
The guest book in Ivan Abeshaus' San Francisco home is filled with thank you notes from Airbnb guests who have rented a room here -- illegally-- up until now.
"I knew that it was not legal, I knew that it was slightly out of compliance with the code," Abeshaus told KTVU Monday.
Abeshaus on Monday signed up with the city's planning department. The law aims to address the rapid growth of home and room-share services such as Airbnb.
"We've had about 300 calls so far. We have appointments scheduled between now and April," said San Francisco Planning Department Communications Manager Gina Simi. "The intent is to provide members of the public who are looking to rent their residential unit out within the boundaries of the new legislation; give them a register number to legally and lawfully rent out their unit."
Participants must provide a business registration certificate along with proof of at least $500,000 in liability insurance. Residents must live in their home for 275 days per year. Units typically rented at below market rate are not eligible for short-term rentals.
The entire process takes about two weeks and costs about $50. Participants receive a registration number they must display on their listing.
"We're on a complaint-based process, so we certainly don't go out looking for people who are participating or not participating in the registry," said Simi.
That's a problem, said San Francisco Supervisor David Campos, who voted against the ordinance last fall.
"If you don't have a way of actually enforcing those regulations and rules, those regulations become a paper tiger," explained Campos.
Campos says the new law also doesn't address the millions in back taxes owed to the city by Airbnb and will help further deplete the supply of affordable rental units.
"And in a housing crisis like the one we're facing, that is only going to make things worse," said Campos.
For Abeshaus, registration is bringing a sense of security.
"We've had a really positive experience over the years," Abeshaus said. "And the only risk was that I felt bad we were breaking the law."