How Might Changes to the ACA Marketplace Impact Enrollees with Mental Health Conditions?

Marketplace enrollment has grown substantially in recent years, increasing from 11.4 million people in 2020 to 24.3 million in 2025. Insurance coverage is a key determinant in accessing health care services, including mental health services. However, several pending policy changes, such as the One Big Beautiful Bill Act (OBBBA) and the expiration of enhanced premium tax credits, may lead to an additional 8.2 million people losing their Marketplace coverage and becoming uninsured by 2034, according to the Congressional Budget Office (CBO). This potential coverage loss raises concerns about access to mental health care services. One in five Marketplace enrollees report that their mental health is “fair” or “poor”, based on a KFF survey. This brief estimates the number of current Marketplace enrollees with a mental health diagnosis – identified as individuals with a health care claim that included at least one mental health diagnosis – to understand what changes in enrollment may mean for access to services, using 2022 health care claims data from the Center for Medicare and Medicaid Service.

Among Marketplace enrollees, more than 1 in 6 (18.2%) had at least one mental health diagnosis on a health care claim in 2022 (Figure 1). However, the share of Marketplace enrollees with a mental health condition is likely higher. This estimate only captures diagnoses for people with a mental illness diagnosis recorded in their medical claims. This estimate does not account for enrollees with only prescription drug claims for a mental health condition, enrollees with undiagnosed mental health conditions, enrollees in remission from mental health conditions, or those who did not seek treatment for their mental health conditions. Additionally, not all individuals are screened for mental illness, and diagnoses are not always recorded on healthcare claims. Prevalence rates estimated through surveys are generally higher than the prevalence rates observed in claims data. A prior KFF analysis found that among adults – regardless of insurance status – reporting moderate or severe symptoms of anxiety and/or depression, 39% did not receive treatment.

Among the 24.3 million Marketplace enrollees in 2025, over 4.4 million individuals are estimated to have at least one mental health diagnosis on a health care claim (Figure 2). Given that 18.2% of Marketplace enrollees had a health care claim with a mental health diagnosis in 2022, approximately 4.4 million enrollees may seek services associated with a mental health diagnosis in 2025. These mental health diagnoses include, but are not limited to, anxiety disorders (3.0 million), depression disorders (2.0 million), trauma and stressor related disorders (0.9 million), and bipolar disorders (0.3 million). Further, mental health conditions often co-occur. Among Marketplace enrollees with at least one mental health diagnosis, 39% will have health care claims that include two or more mental health diagnoses.

Among Marketplace enrollees, mental health diagnoses were most common among adults ages 26-34 and females (Figure 3). Female Marketplace enrollees were more likely to have a health care claim that included a mental health diagnosis than males (22.8% vs. 12.8%). A prior KFF analysis found that men with moderate to severe symptoms of anxiety and/or depressive disorder were more likely than women to not receive mental health treatment, and as a result not receive a mental health diagnosis in the year. Over one-in-five enrollees ages 26-34 (21.6%) had a health care claim that included a mental health diagnosis, followed by enrollees ages 35-49 and 50-64 (19.5% and 19.2% respectively).

The Congressional Budget Office estimates that up to 8.2 million more people will be uninsured in 2034 as a result of changes to Marketplace coverage, which may affect many enrollees with mental health conditions. Several aspects of Marketplace plans created under the Affordable Care Act have allowed for improved access to mental health and substance use services, including classifying these services as essential health benefits, providing coverage for individuals with pre-existing conditions, including mental health conditions, and parity protections. Access to these Marketplace plans has increased with record enrollment in recent years driven in part by enhanced premium tax credits that lowered costs for most enrollees, as well as policy changes that made it easier to sign up for coverage. However, several pending policy changes, including the OBBBA, recently passed by the House, along with the expiration of enhanced premium tax credits, and provisions in a new CMS Marketplace Integrity and Affordability rule may lead to an additional 8.2 million people losing their Marketplace coverage and becoming uninsured by 2034. This would mean if enrollees with mental health conditions lose coverage at a similar rate as other Marketplace enrollees, over one million more people with a mental health diagnosis could be uninsured in 2034. Separately, CBO estimates that changes to Medicaid via the OBBBA would further increase the number of uninsured people by 7.8 million. Medicaid plays a large part in coverage and treatment of behavioral health conditions, covering nearly one-third of all adults with mental health disorders.

Health care expenditures for those with mental health conditions are higher than those without, making insurance an important part of affording treatment for people with mental health conditions. Insured adults with moderate to severe symptoms of anxiety and/or depression are significantly more likely to receive mental health care compared to their uninsured counterparts (64% vs. 38%) in 2019, highlighting the key role insurance coverage plays in linking individuals to mental health care. Among privately insured individuals, those with anxiety and/or depression face higher out-of-pocket costs annually than their peers without a mental health diagnosis ($1,501 vs. $863 in 2021). Reflecting these financial burdens, a 2023 KFF survey found that 43% of insured adults with “fair” or “poor” mental health said they didn’t get needed mental health care because they couldn’t afford the cost. Loss of insurance coverage would further exacerbate the financial burden of seeking mental health treatment.