INTRODUCTION: This study explores how human papillomavirus vaccination initiation and completion among men and women aged 18-34 years varies by geographic region. METHODS: Data from the 2015-2017 Behavioral Risk Factor Surveillance System were analyzed. Geographic regions for the selected states were defined as South, Northeast, and Midwest/West. Human papillomavirus vaccination initiation was defined as receipt of ≥1 dose, and completion was defined as receipt of ≥3 doses. Weighted, multivariable logistic regression models estimated the association between geographic region and vaccine uptake, adjusting for sociodemographic, health, and healthcare factors. Analyses were performed in November 2019. RESULTS: A total of 18,078 adults were included in the study, 80% of whom resided in the South. The overall vaccination initiation rate was 23.4%, and the completion rate was 11.0%. Initiation was higher among those who resided in the Northeast (38.6%), followed by Midwest/West (23.8%), and lowest for those in the South (21.8%) (p<0.0001). Completion rates followed the same trend as initiation. In the adjusted models, compared with the adults residing in the Northeast, those living in the South were less likely to initiate (AOR=0.47, 95% CI=0.40, 0.55) and complete (AOR=0.56, 95% CI=0.46, 0.68) human papillomavirus vaccination. CONCLUSIONS: Human papillomavirus vaccine uptake was low for all regions, but vaccine uptake was significantly lower in the South region. This demonstrates the need to identify barriers specifically associated with the Southern population, which may include differing levels of education and insurance. Such work is especially pertinent because many Southern states face increased risk of human papillomavirus-associated cancers such as cervix and oral cavity and pharynx cancers.