Abstract Introduction: Amid increasing rates of electronic cigarette (e-cigarette) use in the United States, there is an urgent need to monitor patterns of use at the population level in order to inform prac- tice, policy and regulation.This article examines how patterns of e-cigarette use among adults dif- fer between users and nonusers of cigarettes using the most current national data. Methods: We analyzed data from the 2014 National Health Interview Survey. We estimated prev- alence of ever, current, and daily e-cigarette use and examined how use patterns differed by demographic subgroups and measures of cigarette smoking status that accounted for the recent availability of e-cigarettes in the US marketplace. Results: Current e-cigarette use is extremely low among never cigarette smokers (0.4%) and for- mer smokers who quit cigarettes 4 or more years ago (0.8%). Although e-cigarette experimentation is most common among current cigarette smokers and young adults, daily use is highest among former smokers who quit in the past year (13.0%) and older adults. Compared to daily cigarette smokers, recently quit smokers were more than four times as likely to be daily users of e-cigarettes (AOR: 4.33 [95% CI: 3.08–6.09]). Conclusions: Extremely low e-cigarette use among never-smokers and longer term former smok- ers suggest that e-cigarettes neither promote widespread initiation nor relapse among adults. Recognition of the heterogeneity of smokers, including the time since quitting, is critical to draw accurate conclusions about patterns of e-cigarette use at the population level and its potential for public health bene t or harm. Implications: Data from 2014 National Health Interview Survey indicate that e-cigarettes have not been attracting adult non-smokers or promoting relapse in longer term former smokers. Moreover, the data are suggestive that some recent quitters may have done so with the assistance of e-ciga- rettes. Creating measures of smoking status that treat former smokers as a homogenous group is insuf cient to assess the epidemiology of e-cigarette use and the potential impact on public health.