Opioid use, diagnoses of opioid use disorder among pregnant women, and complications from in utero opioid exposure increased dramatically over the past two decades. Despite evidence that medications for opioid use disorder are highly effective for preventing adverse outcomes from opioid use disorder, most patients needing treatment do not receive it with evidence of differential patterns of access for minoritized racial and ethnic groups compared to non-minoritized groups. Disparities in opioid use disorder treatment and medication access may intersect with race and ethnicity and pregnancy status for women seeking treatment for opioid use disorder. Receiving treatment for opioid use disorder during pregnancy is crucial for maternal and infant health and wellbeing; however, issues of equitable treatment access for racial and ethnically minoritized women remains understudied. Extending the ongoing NIDA-funded project (R01DA045729), which conducted a randomized field experiment of pregnant and non-pregnant “secret shoppers” attempting to obtain appointments at opioid treatment programs or with outpatient buprenorphine providers, this health equity supplement seeks to determine if non-white patients identified barriers to obtaining an appointment for opioid use disorder treatment. In addition, we seek to determine if racial concordance was a determining factor in women’s reported experiences based on secret shoppers’ race/ethnicity matching with community setting of clinic locations. Explanations of underlying mechanisms of these barriers will be explored using qualitative data. Leveraging the unique data from the NIDA-funded field experiment, this study will 1) determine if racial concordance between secret shoppers and the communities that surround clinic locations influenced their ability to a) obtain an appointment for treatment, b) wait time for treatment, c) out of pocket costs for treatment, and d) determine if these outcomes varied by pregnancy status and treatment provider type, and 2) explore secret shoppers’ qualitative descriptions of racial discriminatory encounters and experiences when seeking treatment and medication at opioid treatment program, either with opioid treatment programs or outpatient buprenorphine providers, attending to variability based on race/ethnicity and pregnancy status. Data from this study will inform future studies aimed at mitigating health inequities at the confluence of opioid use disorder, pregnancy, and race.