Introduction: RSV infections can lead to serious outcomes, especially among older adults. Two United States (US) Food and Drug Administration (FDA) approved vaccines, both requiring reconstitution (VRR) prior to administration, are recommended by the Advisory Committee on Immunization Practices (ACIP) for adults aged 60+ years. An alternative vaccine employing a ready-to-use prefilled syringe (PFS) is currently under evaluation by the FDA. The current study compared a PFS versus two VRRs (VRR1 and VRR2) to evaluate preparation time, errors, satisfaction, and preference in a randomized, single-blinded time and motion (T&M) study. Methods: Participants were recruited and randomized to a preparation sequence of the three vaccines. Participants read instructions, then consecutively prepared the three vaccines with a 3- to 5-minute washout period in between. Preparations were video recorded and reviewed by a trained pharmacist for preparation time and errors using predefined, vaccine-specific checklists. Participant demographics, satisfaction with vaccine preparation, and vaccine preference were recorded. Within-subjects analysis of variance (ANOVA) was used to compare preparation time. Mixed-effects Poisson and ordered logistic regression models were used to compare number of preparation errors and satisfaction scores, respectively. Results: 63 pharmacists (60%), nurses (35%), and pharmacy technicians (5%) participated at four sites in the US. The least squares (LS) mean preparation time per dose for PFS was 141.8 seconds (95% CI:156.8, 126.7; p<0.0001) faster than for VRR1, 103.6 seconds (118.7, 88.5; p<0.0001) faster than for VRR2, and 122.7 seconds (95% CI: 134.2, 111.2; p<0.0001) faster than the pooled VRRs. Overall satisfaction (combined "Very" and "Extremely") was 87.3% for PFS, 28.6% for VRR1, and 47.6% for VRR2. Most participants (81.0%) preferred the PFS vaccine. Conclusion: PFS vaccines can greatly simplify the vaccine preparation process, allowing administrators to prepare up to four times more doses per hour than with vial and syringe systems.