Problem/Objective: Clean indoor air laws decrease smoking prevalence and cigarette consumption, but it is not known whether or how such policies impact utilization of cessation programs. On 11/8/05, Washington State (WA) voters passed a comprehensive clean indoor air law (Initiative 901) which was implemented 30 days later. Methods: This study analyzes registration data of WA residents who enrolled in the Free & Clear telephone-based quit line program before and after passage of I-901 to assess changes in enrollment volumes and characteristics of enrollees. Results: Enrollment volume was 63% higher in the two months following implementation of the public ban than it was during the same time period the previous year. Data from 6164 callers who registered between 9/8/05-1/8/06 showed that those who called two months after the law was passed were heavier smokers compared to those who registered two months prior to the law (18.2 vs. 17.0 cpd; p<.0001). Additionally, an increase in the proportion of enrollees who were in action or maintenance stage was found following passage of the smoke free law (13.9% vs. 9.5%, p<.0001). Conclusions: State-wide smoke-free legislation appears to increase enrollment in a telephone quit line and lead extrinsically motivated, heavier smokers to seek cessation services. These findings can help treatment programs modify staffing and tailor services to meet changes in demand resulting from such a policy. Further research is needed to assess the long term impact of smoke-free laws on motivation to make quit attempts, utilization of different treatment options and ultimate cessation outcomes.