OBJECTIVES: The aim was to evaluate smoking cessation treatment success and factors associated in older adults. METHODS: In the retrospective cohort study, the patients' sociodemographic data, smoking history, Fagerström Test for Nicotine Dependence scores (FTND), type of treatments (Pharmacological treatments, behavioral counseling, and/or both) and the number of follow-up sessions in the Smoking Cessation Outpatient Clinic were taken from hospital files of the patients. Treatment success was evaluated as one year of abstinence from smoking. RESULTS: Participants' reported with 53% classified as high-very high nicotine dependence. Overall, 36% reported abstinence from smoking for one year or more. Treatment success was associated with higher attendance at follow-up sessions. Using pharmacologic treatments and behavioral counseling together was proved to be more effective than behavioral counseling alone. CONCLUSIONS: One-year smoking cessation was achieved in one-third of older adults attending a smoking cessation clinic. In older adults in this sample low FTND scores, use of combined pharmacologic and behavioral treatment, and attendance at follow up sessions were associated with one year smoking abstinence. CLINICAL IMPLICATIONS: Older adults should be referred for smoking cessation treatment. Use of combined pharmacological and behavioral counseling is recommended. Efforts to enhance attendance at follow-up sessions should be considered.