While the COVID-19 pandemic disrupted healthcare delivery everywhere, persons with carceral system involvement and opioid use disorder (OUD) were disproportionately impacted and vulnerable to severe COVID-associated illness. Carceral settings and community treatment programs (CTPs) rapidly developed protocols to sustain healthcare delivery while reducing risk of COVID-19 transmission. This survey study assessed changes to OUD treatment, telemedicine use, and re-entry support services among carceral and CTPs participating in the National Institute on Drug Abuse (NIDA)-funded study, Long-Acting Buprenorphine vs. Naltrexone Opioid Treatments in Criminal Justice System-Involved Adults (EXIT-CJS) study. In December 2020, carceral sites (n = 6; median pre-COVID 2020 monthly census = 3468 people) and CTPs (n = 7; median pre-COVID 2020 monthly census = 550 patients) participating in EXIT-CJS completed a cross-sectional web-based survey. The survey assessed changes pre- (January-March 2020) and post- (April-September 2020) COVID-19 in OUD treatment, telemedicine use, re-entry supports and referral practices. Compared to January-March 2020, half of carceral sites (n = 3) increased the total number of persons initiating medication for opioid use disorder (MOUD) from April-September 2020, while a third (n = 2) decreased the number of persons initiated. Most CTPs (n = 4) reported a decrease in the number of new admissions from April-September 2020, with two programs stopping or pausing MOUD programs due to COVID-19. All carceral sites with pre-COVID telemedicine use (n = 5) increased or maintained telemedicine use, and all CTPs providing MOUD (n = 6) increased telemedicine use. While expansion of telemedicine services supported MOUD service delivery, the majority of sites experienced challenges providing community support post-release, including referrals to housing, employment, and transportation services. During the COVID-19 pandemic, this small sample of carceral and CTP sites innovated to continue delivery of treatment for OUD. Expansion of telemedicine services was critical to support MOUD service delivery. Despite these innovations, sites experienced challenges providing reintegration supports for persons in the community. Pre-COVID strategies for identifying and engaging individuals while incarcerated may be less effective since the pandemic. In addition to expanding research on the most effective telemedicine practices for carceral settings, research exploring strategies to expand housing and employment support during reintegration are critical.