IntroductionIn observational studies, vaping daily is positively associated with cigarette smoking abstinence, while non-daily vaping is associated with less smoking abstinence (versus no e-cigarette use). It remains unknown whether cigarette smokers who vape daily have different motivations for using e-cigarettes than those who vape non-daily. MethodsUsing latent class analysis and 10 self-reported reasons for vaping, we identified sub-groups of participants based on vaping motivations among 1544 adult (≥18 y) dual users of e-cigarettes and cigarettes at wave 4 of the Population Assessment of Tobacco and Health (2016–2018). We examined the association of motivation sub-groups with vaping frequency at wave 4, and subsequent cigarette smoking abstinence at wave 5 (2018–2019). Additional analyses examined the association of vaping frequency with smoking abstinence before and after adjustment for motivation sub-groups. ResultsFour distinct sub-groups of e-cigarette users emerged, including 54 % of participants who were “Vaping Enthusiasts”, 20 % who vaped for “Convenience and Social Acceptability”, 10 % classified as “Experimenters”, and 16 % who vaped for “Quitting Smoking and Harm Reduction.” The Convenience and Social Acceptability sub-group were less likely than “Vaping Enthusiasts” (AOR=0.29, 95 %CI[0.20–0.42]) and “Quitting Smoking and Harm Reduction” (AOR=0.41, 95 %CI[0.24–0.71]) classes to vape daily (versus non-daily). Sub-groups were not associated with smoking abstinence after one year. Adjustment for motivation sub-groups did not attenuate a positive association of daily vaping with smoking abstinence. ConclusionsCigarette smokers who vaped for convenience and social acceptability were less frequent e-cigarette users than those with other vaping motivations. Vaping motivations were not associated with subsequent smoking abstinence.