Ice-nucleating particles (INPs) can influence multiple climate-relevant cloud properties by triggering droplet freezing at relative humidities below or temperatures above the freezing point of water. The ocean is a significant INP source; however, the specific identities of marine INPs remain largely unknown. Here, we identify 14 ice-nucleating microbes from aerosol and precipitation samples collected at a coastal site in southern California, two or more of which are likely marine.