The Facts

It's about to get easier to build. Mayor Lurie and Supervisor Mahmood just introduced the BUILD Act to cut San Francisco’s transfer tax on multifamily residential buildings in half, plus a companion ballot measure to end a foreclosure/deed-in-lieu exemption to ensure it's revenue neutral. City Hall estimates the change will save builders about $32,000 per home.

This matters because the people who build apartments don’t operate them long-term—they build and sell to a building operator. So a transfer tax on that first sale functions like a legally mandated increase in construction costs.

The Context

Dean Preston's Prop I (2020) doubled the tax rates, which was pitched as a "mansion tax" but excluded mansions and taxed multifamily buildings (like apartments) instead. This effort undoes Dean Preston's signature accomplishment.

In March 2024, voters approved charter changes letting the Board reduce the tax.

The stakes are huge: City Hall has warned of 52,000 approved units stuck in limbo, tracked in the Planning Department’s pipeline report.

The GrowSF Take

The theory of taxation is simple: tax something you want less of, and Dean Preston wanted less housing.

Transfer taxes on big multifamily transactions hit the financing math that determines whether apartments get built. This reform is a practical way to reduce deal friction and unlock housing starts.