Almost 20% of Californian smokers do not smoke daily. Although occasional (non-daily) smoking occurs during uptake, a stable pattern of occasional smoking may imply a milder level of nicotine addiction. We use a longitudinal population sample of smokers interviewed in both 1990 and 1992 to evaluate the stability of occasional smoking. Further, we use 1992 data, including smokers only interviewed in 1992, to compare occasional smokers who have (ever-daily) and have not (never-daily) smoked daily for at least 6 months, and contrast them to daily smokers for key variables associated with addiction. All our analyses exclude uptake smokers. Two-thirds of never-daily occasional smokers in 1992 also smoked occasionally in 1990, compared to only about 40% of ever-daily occasional smokers. Never-daily occasional smokers smoke less than ever-daily ones. They are more often under age 40 years, of Hispanic origin, and were more likely to begin regular smoking beyond their teen years. Demographically, ever-daily occasional smokers were similar to daily smokers except for being more educated. However, both ever-daily and never-daily smokers differed from daily smokers with respect to long-term quitting history, plans to quit, confidence they could quit, and belief they are addicted to cigarettes. Our findings suggest that occasional smoking can be a stable pattern for long periods. Occasional smokers, particularly never-daily ones, appear to be much less addicted to nicotine than daily smokers.