With nearly a third of California’s low-income households living in large (5+ unit) multifamily housing, electrifying and deploying advanced electric technologies to this portion of the housing stock is critical to reaching the state’s goals for equitable climate action. Formulating policies and programs tailored to this segment’s specific housing characteristics is critical to achieving speed and scale in building electrification, yet there is a gap in statewide data on the characteristics of low-income multifamily housing. This Low-Income Multifamily Housing Characteristics Study analyzed the physical characteristics of this housing stock and occupant demographics utilizing Census data (American Community Survey, American Housing Survey) and other public data sources (Low-Income Energy Affordability Tool, Residential Energy Consumption Survey). It also conducted a field study of affordable multifamily buildings in the Bay Area to fill gaps in building-level characteristics not available in public data sources and assess prevalence of factors known to be key barriers to electrification in multifamily housing, such as the need for electrical system upgrades (wiring, circuit panels, service lines) and space constraints. Finally, it gathered input from existing programs serving this market segment with energy efficiency and electrification measures and other stakeholders. Findings from the market characterization, field study, and stakeholder engagement were used to inform recommendations for technology development and program strategies and needs for electrifying this market segment.