San Francisco has strict regulations for short-term rentals (STRs), particularly concerning non-owner-occupied properties. Here are the key rules:

• Primary Residence Requirement: To legally operate a short-term rental, the property must be the host's primary residence. This means the host must live in the unit for at least 275 nights per year. Non-owner-occupied properties are not eligible for STRs, with very few exceptions134.
• Unhosted Rentals: Even for primary residences, unhosted rentals (where the host is not present) are limited to a maximum of 90 nights per year. This restriction aims to prevent residential properties from being converted into full-time vacation rentals13.
• Licensing and Certification: Hosts must obtain a Short-Term Residential Rental Certificate from San Francisco's Office of Short-Term Rentals. This includes submitting proof of residency, liability insurance (minimum $500,000), and paying a $450 application fee15.
• Tax Compliance: Hosts are required to collect and remit a 14% Transient Occupancy Tax (TOT) on their rental income. Platforms like Airbnb often handle this on behalf of hosts13.
• Prohibited Properties: Certain types of units cannot be used for STRs, including:
  • Below-Market-Rate (BMR) or public housing units
  • Single-Room Occupancy (SRO) units
  • Accessory Dwelling Units (ADUs)
  • Properties in areas like Treasure Island, Fort Mason, or The Presidio45.

San Francisco enforces these rules rigorously, with penalties for non-compliance including fines and potential revocation of STR certificates13.