OBJECTIVES: A prescription synchronization and medication management program has been implemented in several community pharmacies to enhance medication adherence and provide greater efficiency in the pharmacy.  The objectives of this analysis were to examine the impact of the program on chronic medication adherence and healthcare costs. METHODS: A cross-sectional analysis using Mississippi Medicaid claims from 2008-2011 was undertaken. Claims for three drug-classes including statins, antihypertensives, and oral hypoglycemics were extracted from a pharmacy that implemented the program and the other pharmacies serving patients in the same geographic area.  First, a retrospective matched cohort analysis was undertaken to compare medication adherence measured as the proportion of days covered (PDC) and medical costs 3, 6, 9, and 12 months from the index date. Patients in the two groups were matched on age, gender, and race using a greedy-match algorithm. Second, a pre-post analysis comparing medication adherence and costs was conducted before and after the enrolling in the target pharmacy program. RESULTS: In the matched analysis, the average PDC three months (90.87% vs. 84.27%; p=0.002) and six months (87.91% vs. 81.86%; p=0.01) after the index date was significantly higher in the target pharmacy group than in the other group.  Average medical costs 3 months ($2,326.52 vs. $1,802.41; p<0.0001) and 12 months ($7,505.36 vs. $7,446.77; p=0.04) after the index date were significantly higher in the other pharmacy group than in the target pharmacy group.  In the pre-post analysis, the average PDC before enrolling in the target pharmacy service was significantly lower than after enrollment (70.3% vs. 84.2%; p<0.0001).  In addition, average medical costs per patient per month significantly reduced from $584 in the pre-period to $420 in the post-period (p<0.0001). CONCLUSIONS: The new service was not only associated with improved medication adherence, but also with decreased medical expenditures among chronic patients.