Electronic cigarettes are gaining in popularity as an alternative to regular cigarettes and for potential in aiding cessation efforts among smokers. Objective: This study seeks to extend previous research and examine longitudinal trends in e-cigarette awareness and perceived harmfulness in association with intention to quit. Design: Data from three administrations of the Health Information National Trends Survey (HINTS 4 Cycles 2-4) were combined into a single dataset for multi-year analysis spanning 2012-2014. Results: Overall awareness of e-cigarettes increased from 77.1 percent in 2012 to 85.4 percent in 2013, and 94.3 percent in 2014. Perception of e-cigarette harmfulness declined slightly from 50.7 percent in 2012 to 47.6 percent in 2014. Older respondents were increasingly less likely to be aware of e-cigarettes than those in the referent group of 18-34 year olds. Racial minorities had lower odds of being aware of e-cigarettes than whites. Females and minority races were less likely to believe that e-cigarettes were less harmful than regular cigarettes compared to males and whites respectively. E-cigarette awareness and perceived harm were not found to be associated with intention to quit smoking. Conclusions: The two additional survey years since the original study have shown continued increase in overall public awareness of e-cigarettes. Still, no relationships between awareness and intention to quit or perceived harm and intention to quit were found in the extended analysis.