Background: According to transtheoretical model (TTM), Stage matched interventions are more effective in quitting. The objective of current study was to investigate the effect of individual counseling, line follow-up, and free nicotine replacement therapy (NRT) on smoking cessation in smokers who are in preparation stage of smoking. Materials and Methods: In a randomized clinical trial design, through sending the short message system, potential participants in preparation stage of smoking were recruited and divided into control (n0 = 60)and treatment ( n = 50) groups. The treatment group received an in-person counseling, line follow-up, and free NRT. TTM variables trend; pros and cons of smoking, behavioral and experiential processes, temptation, were assessed at baseline, 3 and 6 months follow-up along with point prevalence and continuous abstinence. Results: Continuous abstinence at 6-month follow-up were 3.3% ( n = 2) in control group and 46% ( n = 23) in the treatment group ( x2 = 34.041, P < 0.001). Time Χ group analyses indicated that except cons of smoking ( P > 0.05), all TTM constructs had significantly changed; temptation ( F = 36.864, P < 0.001), pros ( F = 12.172, P < 0.001), experiential processes ( F = 3.377, P < 0.001), and behavioral processes (F = 11.131, P < 0.001). Conclusion: Interventions based on TTM variables increased the quite rate in prepared and motivated people. Our findings suggest that interventions through individual counseling along with free NRT and line follow-up in people who prepare for quitting are beneficial for our country.