The basic cigarette smoking status questions consisted of two parts: (1) "Have you smoked at least 100 cigarettes during your entire life?" If yes, "Do you smoke cigarettes now?"

A person was considered to have never smoked or was a nonsmoker if he did not smoke more than 100 cigarettes during his entire life. Respondents who ever smoked more than 100 cigarettes in their entire lives were classified as "ever smokers" and were further categorized into current or former smokers. Current smokers were those who reported smoking from less than one cigarette per day to 99 or more cigarettes per day. A former smoker was anyone who has smoked at least 100 cigarettes during his entire life did not smoke at the time of the interview.

For 1985 and 1990, the term "regular smoker" was respondent defined (Interviewers were instructed to "accept the respondent's interpretation of "fairly regularly.")

In 1991, current smokers were divided into "everyday" smokers or "someday" smokers). That year, the NHIS started to distinguished smokers who smoked daily from those who smoked less often than daily. Those who said "no" to the current smoking status question, were asked, "Do you smoke some days or not at all?" This additional follow-up resulted in the classification of persons as "someday smokers" who would otherwise have been considered former smokers, since they initially said that they did not smoke now.