Nicotine withdrawal is cited by smokers as a principal reason for relapse and a significant barrier to sustained abstinence. Postcessation self-efficacy is established as a predictor of smoking cessation success but may be influenced by the impact of nicotine withdrawal symptoms. The objective of the current study was to determine if the relationship between nicotine withdrawal and relapse to smoking was mediated by diminished postcessation self-efficacy. Smokers (N = 266) ready to make a quit attempt completed measures of nicotine withdrawal, depressed mood and self-efficacy at Week 1
post-target quit date (TQD); smoking status was collected at Week 3 post-TQD. Both nicotine withdrawal (OR = 0.56, CI = 0.36-0.85, p <.01) and self-efficacy (OR = 1.50, CI = 1.09- 2.05, p <.05) predicted continuous abstinence at Week 3; depressed mood did not. Mediational analysis did not support the contention that self-efficacy mediated the role of nicotine withdrawal on abstinence.