Quitting smoking after a diagnosis of cancer results in greater response to treatment and decreased risk of disease recurrence and second primary cancers. The objective of this study was to evaluate the potential cost-effectiveness of two smoking cessation approaches: the current basic smoking cessation program consisting of screening for tobacco use, advice, and referral; and a best practice smoking cessation program that includes the current basic program with the addition of pharmacological therapy, counseling, and follow-up. A Markov model was constructed that followed 65-year-old smokers with cancer over a lifetime horizon. Transition probabilities and mortality estimates were obtained from the published literature. Costs were obtained from standard costing sources in Ontario and reports. Probabilistic and deterministic sensitivity analyses were conducted to address parameter uncertainties. For smokers with cancer, the best practice smoking cessation program was more effective and more costly than the basic smoking cessation program. The incremental cost-effectiveness ratio of the best practice smoking cessation program compared to the basic smoking cessation program was $3367 per QALY gained and $5050 per LY gained for males, and $2050 per QALY gained and $4100 per LY gained for females. Results were most sensitive to the hazard ratio of mortality for former and current smokers, the probability of quitting smoking through participation in the program and smoking-attributable costs. The study results suggested that a best practice smoking cessation program could be a cost-effective option. These findings can support and guide implementation of smoking cessation programs.