This pilot randomized controlled trial examined the feasibility and acceptability of a motivational interview (MI)-enhanced safety planning intervention (MI-SafeCope) for teens hospitalized due to suicide risk and explored proximal outcomes (possible mechanisms of change). Participants were 36 hospitalized adolescents (ages 13-17; 78.8% female) with last-week suicidal ideation and/or past-month suicide attempts. Adolescents were randomized to MI-SafeCope, a three-component intervention (individual and family sessions, postdischarge call), or to treatment as usual. Primary outcomes were feasibility and acceptability. We also explored differences in proximal outcomes assessed at 2 weeks, 1 month, and 3 months (family connectedness, motivation for safety plan use, parental motivation to encourage safety plan use), as well as daily for 4 weeks (self-efficacy, coping behavior, safety plan use). Participation and retention rates and intervention satisfaction ratings indicate feasibility and acceptability. Mixed-effects models of daily assessments indicated, for the MI-SafeCope group, significantly higher self-efficacy to refrain from suicidal action (B = 1.15, p = .030), greater reliance on self to cope with suicidal ideation (B = 1.56, p = .042), and higher likelihood of safety plan use to manage suicidal thoughts (B = 0.25, p = .004). Parents in the MI-SafeCope group reported higher motivation to encourage safety plan use (B = 1.04, p = .031). Safety planning incorporating MI is feasible and acceptable with hospitalized teens. Preliminary findings suggest that MI strategies may be promising in maintaining adherence to safety plans, increasing self-efficacy and coping, and in fostering parents' motivation to encourage safety plan use. Our study also highlights the benefit of daily-level assessment of individuals' response to suicide-specific interventions.