Purpose This study explores correlates of on‐site availability of substance use disorder treatment services in federally qualified health centers, including buprenorphine treatment that is critical to addressing the opioid epidemic. Methods We employed descriptive and multivariable analyses with weighted 2010 Assessment of Behavioral Health Services survey data and the 2010 Uniform Data System. Findings In 2010, 47.6% of health centers provided on‐site substance use disorder treatment, 12.3% provided buprenorphine treatment for opioids, and 38.8% were interested in expanding buprenorphine availability. Urban health centers, those in the West, and health centers with electronic health records had higher odds of offering on‐site substance use disorder treatment. Compared with on‐site mental health treatment, substance use disorder treatment was available in fewer clinic sites within each organization. Health centers in rural areas had lower odds of providing on‐site buprenorphine treatment (OR = 0.49, 95% CI: 0.26‐0.94), and those in the South had lower odds of providing on‐site buprenorphine treatment compared with health centers in other regions. Rural health centers had lower odds of expressing interest in expanding the availability of buprenorphine treatment (OR = 0.58, 95% CI: 0.35‐0.97). Conclusions Improving access to substance use disorder treatment in primary care is a critical part of the strategy to combat the opioid use disorder epidemic. These findings highlight the important role of health centers as portals of access to substance use disorder treatment services in underserved communities. Recent investments to expand treatment capacity in health centers will expand the availability of substance use disorder services, but urban/rural and regional disparities should be monitored.