We’ve often discussed how difficult it is to get insurance companies to cover intensive mental health treatment. Insurers often find reasons to deny this treatment given it can be expensive and protracted. There are existing mental health parity rules intended to combat this problem, but they have been interpreted extremely narrowly by courts.
The Washington State Legislature is attempting to change that. In 2025, the legislature passed important amendments to our state’s mental health insurance parity laws. These amendments make several important changes to protect patients’ access to mental health coverage and treatment.
First, the legislature expressly declares that: “Access to mental health and substance use disorder treatment is critical to the health and well-being of individuals with these conditions.” It further declares that “access to appropriate care is important to reducing preventable emergency department visits [and] hospitalizations.” This recognizes that untreated mental health conditions can escalate and become emergencies.
The legislature also recognizes that health insurance coverage is “essential” to access to mental health care.
Therefore, the amendments declare that the legislature intends to increase acces to mental health treatment by removing certain roadblocks that insurers have placed to coverage for this treatment.
Second, the legislature addresses some of these roadblocks. One battle in procuring mental health treatment coverage concerns the phrase “medically necessary.” Virtually all health plans cover treatment that is medically necessary. This is often a ground for the insurance company to deny coverage.
One big problem for patients is that insurers often deny that treatment is medically necessary using secret and Byzantine internal guidelines.
These disputes often look like this:
Patient: Please cover this treatment. My doctor says I need it to manage my symptoms. Without it, my condition could get worse. I might not be able to keep working. In an extreme worst-case scenario, I might have to be hospitalized.
Insurance Company: Sorry, that’s not “medically necessary.”
Patient: How can it be not medically necessary? My doctor says I need it!
Insurance Company: We don’t really care what your doctor says. We have our own checklist for what’s medically necessary. And our checklist says we don’t have to pay for your treatment. Sorry!
Patient: Will you show me the checklist, so I can review it with my doctor and find out how to get my treatment covered?
Insurance Company: The checklist is secret. Have a great day!
Part of the new law aims to fix this problem. It requires that medical necessity decisions for certain mental health treatment must be made based on “criteria from nonprofit professional associations.” In other words, insurers now have to decide medical necessity for these kinds of treatment based on objective critera from doctors or providers with real-world experience. They can’t simply make up their own criteria.
Further, it requires insurers to disclose meaningful information about coverage denials for medical necessity. The carrier must provide “full details” about “the relevant criteria” used in the decision to the patient and their health care provider.
Additionally, the new law empowers Washington State’s Insurance Commissioner to review any internal criteria health insurance companies use to decide whether to pay for the treatment at issue.
Insurance coverage for mental health treatment will probably be a battle for many years. But these amendments should be a step in the right direction.
Seattle Insurance and ERISA Blog 