In 2023, approximately 17.1 % of those aged 12 or older in the United States meet criteria for a past year substance use disorder (SUD; SAMHSA, 2024). Substance use is a leading contributor to and cause of preventable death (Garnett and Miniño, 2024; Stahre et al., 2014) and costs the United States billions of dollars per year (Peterson et al., 2021; Sacks et al., 2015). Although effective psychotherapy and pharmacotherapeutic treatments exist for many SUDs (Bolívar et al., 2021; Lim et al., 2022; McPheeters et al., 2023), there are significant gaps in care that limit the impact of such treatments on public health. Although not an exhaustive list, people meeting criteria for SUD often do not seek treatment for at least one of three reasons (SAMHSA, 2023). First, many do not perceive a need for treatment, and most resolve alcohol or drug related problems without help from any professional services (Haeny et al., 2024; Tucker et al., 2020). Second, among those interested in services, there is often a lack of availability/accessibility of substance use treatment services, with substantive disparities in rural areas and within marginalized communities (Lin et al., 2020). Specialized services are often residential and require significant financial resources and time to complete, which limits feasibility. This concern is somewhat mitigated by the wide availability of mutual support groups such as alcoholics anonymous (“AA”), narcotics anonymous (“NA”), and self-management and recovery (“SMART”) training, which have been shown to be useful services for some people attempting recovery (Kelly et al., 2020). Third, SUD and treatment is stigmatized, preventing people from seeking recovery support services and treatment that may aid remission from SUD (Cheetham et al., 2022; Luoma et al., 2007; Madden et al., 2021).

Mental illnesses, broadly defined as psychiatric conditions other than SUD, are also common in the United States, with approximately 23.1 % of the U.S. population living with some form of mental illness of ranging severity (SAMHSA, 2023). Mental illness commonly co-occurs with SUD (SAMHSA, 2023), and comorbid clinical presentations are typically more severe compared to either condition alone. Compared to treatment seeking for SUD among those with SUD, People living with any mental illness (AMI) are more likely to seek treatment for their MI, with an estimated 50.6 % seeking some form of mental health treatment in the past year in 2022 (SAMHSA, 2023). Rates of treatment seeking for U.S. adults with both AMI and SUD have been previously reported (SAMHSA, 2023), with 59 % of those with both SUD and AMI receiving treatment. Of these, 38 % receive treatment for mental health but not SUD, 4 % receive treatment for SUD but not mental health, and 17 % receive treatment for both. Other research has found that SUD treatment is associated with past year mental health treatment receipt (Choi and Marti, 2025).

However, there are no published conditional prevalence estimates of mental health treatment seeking among people with SUD. This is important because SUD is stigmatized, and while those with SUD (but not AMI) may be more likely to seek other forms of treatment, this has not been previously reported. Evidence for this would suggest that mental health treatment may be a promising target to address gaps in the SUD cascade of care, or the series of steps a person with SUD may go through in order to receive treatment and sustain recovery (Socías et al., 2016; Williams et al., 2017). Further, rates of treatment seeking for both SUD and AMI may differ by key variables such as sex, race, age, and insurance type, which has also not previously been reported.

In this analysis of nationally representative data, we characterize conditional prevalence rates of mental health treatment seeking among people with a SUD. For comparison, we also examine conditional prevalence of SUD and mental health treatment among those with any mental illness, in addition to treatment for SUD or mental health within the subset of individuals with both a SUD and mental illness.