INTRODUCTIONSmoking is the leading preventable cause of death and illness globally. There is conflicting evidence regarding the association between quitting rates and partners’ smoking status. It is thought that spouses influence one another’s health habits, including smoking. This study aims to evaluate this association in patients who made a smoking cessation attempt with pharmacotherapy.METHODSFor this Israeli nationwide retrospective cohort study, we randomly selected patients who filled a prescription for varenicline as part of their smoking cessation process and were partnered. The participants were asked to complete a questionnaire 26–52 weeks after the first varenicline purchase. The independent variables were the partner’s smoking status at the beginning of the smoking cessation process and while answering the questionnaire. The outcome was a success in the quitting process.RESULTSIn all, 226 (50%) participants had partners who smoked at the beginning of the quitting process, and 230 (50%) had non-smoking partners; 178 (39%) participants reported successful smoking cessation. There was a significant difference in success rates depending on partners’ smoking status at the end of the process, with success rates of 39% with a non-smoking partner, 76% with a partner who also stopped smoking, and 31% with a partner who continued smoking (p<0.001). Multivariate analysis showed that having a partner who stopped smoking during the quitting process was associated with higher odds of quitting compared with having a non-smoking partner (OR=4.73; 95% CI: 1.86–12.05).CONCLUSIONSThis study showed that both partners quitting was associated with increased odds of successful quitting. Health providers should make efforts to engage both partners in smoking cessation.