OBJECTIVE: The goal of this study was to determine changes in antibiotic-dispensing rates among children in 3 health plans located in New England [A], the Mountain West [B], and the Midwest [C] regions of the United States. METHODS: Pharmacy and outpatient claims from September 2000 to August 2010 were used to calculate rates of antibiotic dispensing per person-year for children aged 3 months to 18 years. Differences in rates by year, diagnosis, and health plan were tested by using Poisson regression. The data were analyzed to determine whether there was a change in the rate of decline over time. RESULTS: Antibiotic use in the 3- to <24-month age group varied at baseline according to health plan (A: 2.27, B: 1.40, C: 2.23 antibiotics per person-year; P < .001). The downward trend in antibiotic dispensing slowed, stabilized, or reversed during this 10-year period. In the 3- to <24-month age group, we observed 5.0%, 9.3%, and 7.2% annual declines early in the decade in the 3 plans, respectively. These dropped to 2.4%, 2.1%, and 0.5% annual declines by the end of the decade. Third-generation cephalosporin use for otitis media increased 1.6-, 15-, and 5.5-fold in plans A, B, and C in young children. Similar attenuation of decline in antibiotic use and increases in use of broad-spectrum agents were seen in other age groups. CONCLUSIONS: Antibiotic dispensing for children may have reached a new plateau. Along with identifying best practices in low-prescribing areas, decreasing broad-spectrum use for particular conditions should be a continuing focus of intervention efforts.