In the US, the market share of plug-in electric vehicles (PEVs)—including battery electric and plug-in hybrid electric vehicles—has been rapidly increasing as a variety of new PEVs have been introduced. Knowing where PEV users are located is important to ensure that electric vehicle charging infrastructure is installed in areas where it is needed. Information on PEV location can also inform electricity supply planning to prepare for a future with higher PEV adoption. Previous studies have looked at the spatial distribution of new PEVs but not of used PEVs. Yet these spatial distributions will likely differ because the buyers of used PEVs have different characteristics than new PEV buyers. Therefore, planning charging infrastructure and electricity supply based solely on new PEV data may not serve both new and used PEV buyers. Policies developed to support drivers of used PEVs may ultimately attract a broader group of people into the PEV market, as used vehicles are less expensive than new ones. Researchers at the University of California, Davis used aggregated data at the zip code level to understand where buyers of second-hand PEVs are located, and to explore differences in the location and characteristics of regions with more original owners vs. second owners of PEVs. This policy brief summarizes the findings from that research and provides policy implications.