Little is known about differences between adolescents' and adults' exposure to e-cigarette advertising in various media channels, such as retail establishments, print, television, radio, and digital marketing. We examined the exposure to e-cigarette advertising in these channels amongst adolescents (13-17), young adults (18-25), and older adults (26+). Adolescents ( = 1124), young adults ( = 809), and adults ( = 4186) were recruited through two nationally representative phone surveys from 2014-2015. Lifetime e-cigarette advertising exposure was prevalent (84.5%). Overall, older adult males and older adult cigarette smokers reported the highest exposure to e-cigarette advertising ( < 0.001). Television was the largest source of exposure for all age groups. Adolescents and young adults had higher odds than older adults of exposure through television and digital marketing. However, adolescents had lower odds than young adults and older adults of exposure through retailers and print media. Although e-cigarette advertising appears to be reaching the intended audience of adult smokers, vulnerable populations are being exposed at high rates via television and digital marketing. Regulations aimed at curbing exposure through these media channels are needed, as are counter advertising and prevention campaigns.