INTRODUCTION: Smoking is the leading cause of preventable death in the United States and has been shown to be harmful to human health. Among alternative tobacco products, e-cigarettes have been widely regarded as the safest substitute to the traditional cigarette. However, debate remains about their safety and possible ill effects. AIM: The purpose of this study was to assess characteristics associated with e-cigarette use (everyday/some days/no use) and examine factors related to former smokers replacing a traditional smoking habit with e-cigarette use (yes/no). METHODS: A secondary data analysis was conducted with the Public Use Files (PUFs) for the Population Assessment of Tobacco and Health (PATH) Study, a nationally representative, longitudinal cohort study of tobacco use. Bivariate and multivariable unweighted and weighted generalized linear models were developed for value and comparative purposes, as well as multilevel models to account for within geographical region clustering. Ordinal logistic regression was used to analyze the ordinal e-cigarette use outcome, and logistic regression with the e-cigarette smoking status of former smokers outcome. RESULTS: Covariates associated with e-cigarette use included having rules that allowed smoking non-combustible tobacco inside the home (everyday vs no use: OR = 0.33, CI = 0.27-0.41; somedays vs no use: OR = 0.58, CI = 0.53-0.64), older than 35 years old (everyday vs no use: OR = 0.63, CI = 0.52-0.75; somedays vs no use: OR = 0.86, CI = 0.76-0.96), and positive or neutral self-opinion on tobacco (everyday vs no use: OR = 0.88, CI = 0.73-1.05; somedays vs no use: OR = 1.38, CI = 1.22-1.55). Factors related to e-cigarette use in former smokers included rules allowing non-combustible tobacco products inside the home (Weighted: OR = 0.19, CI = 0.15-0.24; Unweighted: OR = 0.15, CI = 0.12-0.19; Mixed: OR = 0.19, CI = 0.15-0.24), aged 18-35 years (Weighted: OR = 1.45, CI = 1.16-1.80; Unweighted: OR = 2.91, CI = 2.27-3.72; Mixed: OR = 1.45, CI = 1.16-1.80), and not having any health insurance (Weighted: OR = 0.57, CI = 0.44-0.75; Unweighted: OR = 0.47, CI = 0.34-0.64; Mixed: OR = 0.57, CI = 0.44-0.75). DISCUSSION: Family tolerance of smoking and one’s self-opinion on tobacco were factors found to be strongly associated with e-cigarette use. The prevalence of e-cigarette use among young adults raises concerns and necessitates a multi-disciplinary approach to monitor and intervene. Further study is needed to better understand e-cigarette smoking consumption behavior and effects.