We examined whether use of snus influenced cognitions in terms of smoking expectancies and smoking prototype perceptions in a direction that could promote smoking initiation, thus highlighting potential causal mechanisms between the use of snus and smoking behavior. A telephone-based longitudinal survey among Norwegian adolescents was conducted with two points of measurement during a 1-year period in 2006-2007. The respondents were divided into four groups: Group 1: snus initiators during the period (N = 54), Group 2: regular snus users (N = 160), Group 3: non-users of snus and cigarettes (N = 376), and Group 4: regular smokers (N = 306). Wilcoxon tests were applied to determine any changes in smoking cognitions from 2006 to 2007. The group of snus initiators (Group 1) reported a significantly higher level of expectancies of smoking to promote negative affect reduction at follow-up, while all other cognitions remained stable. The group of smokers (Group 4) reported on average positive smoking cognitions, and significant changes were observed during the period. However, among regular snus users (Group 2) and non-users (Group 3), there were no significant changes in any of the smoking cognitions. The uptake of snus might influence expectancies of cigarettes to reduce negative affect in a direction facilitating smoking initiation, but the use of snus does not appear to influence the majority of cognitions known to promote smoking initiation among adolescents.