The human papillomavirus quadrivalent (types 6, 11, 16, and 18) recombinant vaccine is effective in preventing cervical, vulvar, vaginal and anal cancer. Maximal protection is achieved with completion of all three recommended doses. A retrospective chart review was performed to (1) assess the current vaccine series completion rates in a private practice multispecialty suburban setting and (2) identify factors associated with failure to complete the vaccine series. Chi-square and independent samples t test were used for data analysis. A total of 4,117 patients out of 10,821 eligible patients received at least one dose of the HPV vaccine between October 1, 2006 and April 30, 2010. Overall, 69.5 % (n = 2,863) of patients who received one dose of the HPV vaccine completed all three doses in a valid time frame, representing 26.5 % of all eligible patients. Patients who completed the series were younger (16.8 vs. 18.2, p < 0.05), less likely to have a sexually transmitted disease diagnosis prior to initiation of the series (57.7 vs. 69.8 %, p < 0.05), and more likely to have visited the pediatrics department compared to family medicine, internal medicine, and OB/GYN departments (75.9, 65.7, 57.0, 60.9 %, respectively, p < 0.05). Deaths, pregnancies, and adverse drug reactions were not identified as independent factors impacting completion rates. The results indicate that adolescents, patients visiting the pediatrics department and those without a prior STD diagnosis completed the vaccination series more frequently than adults managed in family medicine, internal medicine, and OB/GYN departments.