Abstract Smoking among Latino young adults (18-29) in South Texas is high (23.2% to 25.7%), representing a serious public health problem. Yet few are reached by services to help them quit smoking. Young adult Latinos are heavy users of mobile devices for texting and access to mobile media. These have an extraordinary theoretical potential for assisting smoking cessation by providing peer modeling and eliciting social reinforcement for behavior change. Thus, we are developing bilingual text messaging and mobile media services specifically targeting Latino young adults in South Texas to quit smoking. Methods: Following a six-month preparatory phase of work to finalize promotional plans, develop and pretest evidence-based, culturally tailored English and Spanish SMS (text message) cessation services, we will launch an intensive social and mobile media promotional campaign to recruit 3,000 young adult cigarette smokers to this service. This project's innovative features include attention to a population that has not been served with efforts to promote smoking cessation. We will employ social media (Facebook, Twitter, Instagram and YouTube) for outreach young adults who smoke. Text messages include links to web pages with additional content and YouTube videos with peer modeling of reasons and skills to quit smoking. We are transforming evidence-based SMS cessation assistance methods that have previously been available only in English or with generic Spanish translation, to fit the language use and cultural milieu of young Spanish and English speakers. Preliminary Results: Results of our initial pilot test showed that the Facebook advertising yielded 481,601 impressions and 1,534 unique users clicked join to view the service's home page. The invitation to text a code there resulted in 147 enrollments in the service, at a cost of $37 for each user recruited. Users were all men, with a mean age of 28 and 63% reporting that they were Hispanic or Latino. These users received texts with links to mobile pages addressing reasons for quitting, social support, nicotine replacements, breathing exercises, getting active, things to do instead of smoking, talk yourself out of smoking and binge drinking. On average these service users spent 7.75 minutes consuming the graphic, text and video content on these pages. Conclusion: Preliminary results provide evidence that young adult Latino smokers can be reached via mobile media service. The anticipated outcome is a scalable, culturally relevant, evidence-based and cost-effective service with broad national reach to help young adults of Latinos stop smoking, with the potential to reduce health care costs, reduce chronic disease burden and improve quality of life among this young, fast-growing, at-risk population. The program kickoff is scheduled for September and we will present preliminary results. Citation Format: Amelie G. Ramirez, Patricia Chalela, Kipling J. Gallion, Edgar Muñoz, Cliff Despres, David Akopian, Arely Perez, Robert Garcia, Alfred L. McAlister. Text messaging cessation service for young adult Latinos in South Texas: Program protocol and preliminary results. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr A11.