Background: The elevated rates of ultraviolet radiation (UVR) exposure and low rates of sun protection in young adult women indicate a need for age- and gender-appropriate interventions that address these behaviors. Aims: To examine the effects of daily behavior tracking and individually tailored text messages on sun protection and UVR exposure behaviors in young adult women at moderate to high risk of developing skin cancer. Method: One hundred and four young adult women at risk of skin cancer were randomized to receive the behavior-tracking intervention only, tailored text messages only, both interventions, or neither. Outcomes were self-reported UVR exposure and sun protection behaviors. Results: Those who received the behavior-tracking intervention reported significantly fewer UVR exposure behaviors at 4-week follow-up, relative to those who did not receive behavior tracking. At 4-week follow-up, those who received daily tailored text messages reported significantly greater UVR exposure behaviors but were more likely to report wearing a hat as a form of sun protection, relative to those who did not receive tailored messages. Discussion: Daily behavior tracking may be repetitive, but repetition may facilitate cognitive processing and the development of healthy habits. Health messages that are less interactive, on the other hand, need to be adequately tailored and delivered with the most advantageous timing to be impactful. Conclusion: Future research should continue to examine how these interventions differentially affect behavior and how they can be adapted to apply to other health behaviors.