BACKGROUND There is a need for efficient and effective assessment, prevention, and intervention for alcohol use among older adults (ages ≥50) to reduce health risks and encourage healthy aging. However, most digital interventions for addiction are targeted to and evaluated among adults younger than 50. Given the growing digital literacy of older adults with mobile technologies, mobile messaging offers a promising, low-burden channel to deliver accessible behavioral interventions. METHODS We designed a mobile text messaging program tailored to older adults that include daily self-tracking and messages to encourage moderated drinking. We then conducted an exploratory, fully remote, single-blind randomized controlled study (NCT06126107) comparing three behaviorally designed messaging programs over a period of 8 weeks: gain-framed, loss-framed, and hybrid which alternated gain and loss messaging daily. Participants (N = 105, female = 44 %) were between the ages of 51 and 78 and were recruited through a variety of channels to capture a diverse sample of older adults. We evaluated the feasibility and preliminary effectiveness of these programs to optimize intervention design for future research trials and implementation in clinical practice. RESULTS The mobile messaging programs were effective in reducing the number of heavy drinking days and in decreasing alcohol-related consequences and geriatric depression. Secondary measures, including intent-to-continue the program beyond the treatment period, favored the gain-frame program over the other two programs. Specifically, gain-framed messaging helped participants see both more benefits of drinking at safe level and the consequences of excessive drinking more than the two other programs, even despite the focus of the loss-framed programs on consequences alone. Engagement with the program was high, with more than 70 % of daily self-tracking prompts completed during the 8 weeks intervention period. CONCLUSIONS The current trial shows promise for using mobile messaging to assist in moderating alcohol consumption in aging, with the gain-frame program as the most preferred by participants. Additional behavioral mechanisms should be optimized beyond the dimension of gain and loss framing to increase the effectiveness of mobile messaging and tailoring for older adults.