The United States has a growing need for behavioral health services, particularly since the pandemic, which worsened the longstanding gap between demand for services and available treatment. In 2021, 57.8 million adults had a mental illness and 46.3 million people 12 and older had a substance use disorder. The consequences of untreated illness are myriad, ranging from economic costs to premature and preventable deaths.

Since 2008, the federal Mental Health Parity and Addiction Equity Act (MHPAEA) has sought to make it easier for people to obtain treatment for mental health and substance use disorders by requiring health plans that cover these conditions to do so on par with other health needs. For example, the law prohibits health plans from charging higher copayments, separate deductibles, and/or imposing stricter requirements (e.g., preauthorization or medical necessity reviews) for these services than they do for other covered treatments.

While states have made strides in ensuring individual and group health insurance coverage complies with MHPAEA, challenges remain, particularly for barriers to treatment that aren’t easily measured. States’ efforts are helped by new federal funding for state enforcement and a 2021 federal law requiring insurers to share with regulators their internal documents that show how they designed and applied treatment limits so that mental health and substance use disorder benefits aren’t subject to stricter limits than are other types of medical care.