Access to medication-assisted treatment in the United States: Comparison of travel time to opioid treatment programs and office-based buprenorphine treatment

•Drive time to the closest OBBT was smaller than drive time to the closest OTP.•Compared to urban residents, rural residents spent 2–5 times more time to access OTPs.•Idaho, Montana, North Dakota, South Dakota, and Wyoming had poorest access to OTPs. Disparities in access to medication-assisted treatment are a major problem. This study estimated and compared drive time to the nearest opioid treatment program (OTP) and office-based buprenorphine treatment (OBBT) across the urban-rural continuum in the U.S. Drive time was calculated between the longitude and latitude of population weighted block group centroids and the longitude and latitude of the nearest OTP and OBBT. Rural-Urban Commuting Area (RUCA) codes were used for defining rurality. The Integrated Nested Laplace Approximation approach was used for statistical analysis. The mean travel time to the nearest OBBT compared to OTP decreased by 7.18 min (95 % CI = 7.23−7.14) in metropolitan cores, 36.63 min (95 % CI = 37.12−36.15) in micropolitan cores, 38.84 min (95 % CI = 39.57−38.10) in small town cores, and 40.16 min (95 % CI = 40.81−39.50) in rural areas. Additionally, travel burden to the nearest OTP would be more than 60 min for 13,526,605 people and more than 90 min for 5,371,852 people. The travel burden to the nearest OBBT would be more than 60 min for 845,991 people and more than 90 min for 149,297 people. The mean drive time to the closest OBBT was significantly smaller than the mean drive time to the closest OTP. Analysis of barriers to access is necessary to devising creative initiatives to improve access to critical opioid use disorder treatment services.