It is well established that environmental stimuli influence smoking in light, and to a lesser degree, heavy smokers. A two-factor model of dependence suggests that the influence of stimulus control is masked among heavier smokers who primarily smoke for nicotine maintenance. The current study aimed to assess the influence of stimulus control across a range of moderate to heavy daily smokers. Furthermore, as local tobacco control policies may change the role of stimulus control, the study aimed to replicate previous US findings on stimulus control in an Australian setting marked by strong tobacco control policies. In two Ecological Momentary Assessment studies, 420 participants monitored antecedents of smoking and non-smoking situations. In a set of idiographic logistic regression analyses, situational antecedents were used to predict smoking occasions within each individual’s data. Linear regression analysis was used to test for the association between stimulus control and smoking rate, and to test for differences between the two samples. Daily smokers’ smoking was under considerable stimulus control, which was weaker at higher smoking rates. Overall, there was greater stimulus control in the Australian sample. Daily smokers also experience a degree of stimulus control, which is less influential in heavier smokers.