Pyloromyotomy is a common surgery performed for hypertrophic pyloric stenosis at community and children's hospitals. To determine hospital-level factors that may affect clinical outcomes, infants requiring pyloromyotomy from 1999 to 2007 (n=8379) were retrospectively reviewed from the California linked birth cohort data set. Hospital case volume and type (community, children's, adult hospital with children's unit) were examined. Surgical complications, prolonged length of stay (LOS), and 30-day readmission were analyzed with multivariate logistic regression. Overall, surgical complications occurred in 166 (2%) infants, 35 (21%) after discharge. Readmission occurred in 285 (3.4%) infants with 69 (24%) admitted to hospitals that did not perform the initial surgery. Infants treated at community hospitals (odds ratio [OR], 2.1; 95% confidence interval [CI], 1.1 to 4.0) experienced an increased likelihood of surgical complications. Odds of surgical complications did not vary by hospital case volume. Prolonged LOS was increased at community hospitals (OR, 1.7; 95% CI, 1.2 to 2.3), low- (OR, 2.1; 95% CI, 1.3 to 3.4), and medium-volume (OR, 1.6; 95% CI, 1.0 to 2.7) hospitals. Hospital type and volume did not impact 30-day readmission. In conclusion, specialized surgical care for infants administered at pediatric centers appears to influence pyloromyotomy complications more than hospital case volume. Institutional components contributing to improved outcomes in specialty centers warrant further investigation.