Office to Housing Conversion Act (AB 507)

In response to California’s housing crisis, the State Legislature has introduced numerous bills to fund, incentivize, and legalize new housing. On October 10, 2025, Governor Gavin Newsom signed into law Assembly Bill 507 (AB 507), the Office to Housing Conversion Act. Generally, AB 507 provides a ministerial approval process for adaptive reuse multifamily housing developments on certain properties in exchange for certain amounts of on-site affordable housing and workforce commitments.

What is the Process and What to Expect for Using AB 507?

1. Before submitting an AB 507 application, complete any required tribal notification process. Submit a Notice of
   Intent to begin the tribal notification process. If tribal consultation is requested, it must be completed before you
   submit your AB 507 application.
2. If the existing building is over 50 years old and is a Category B potential historic resource, submit a Historic
   Resources Review Application. The Planning Department will make a determination within 90 days of submittal.
3. If the project involves an existing building or structure listed on a local, state, or federal historic register, or if the
   site is determined to be a historic resource, the Project Sponsor must sign an affidavit confirming the project will
   follow the United States Secretary of the Interior’s Standards for Rehabilitation.
4. Submit a complete AB 507 application package to the Planning Department after completing any required tribal
   notification and historic resource review.
5. Planning Department staff will review the application for completeness within 30 days of submittal.
6. Once the application is complete, the Planning Department will review the project for AB 507 eligibility and
   compliance with objective standards. This review will be completed within 60 days for projects with 150 units or
   fewer, or within 90 days for projects with more than 150 units.
7. Once the project is determined to comply with objective standards, the Planning Department will approve or
   deny the application within 60 days for projects with 150 units or fewer, or within 90 days for projects with more
   than 150 units. Time that the sponsor spends on revisions to the project as a result of compliance or completion
   requests do not count toward State timelines for review.
8. If approved, certain requirements, including workforce requirements, Phase 1 environmental review and
   mitigation, and replacement dwelling unit requirements,