When you need a therapist the most, you’re probably not willing to spend a lot of time to find one.

In the US, the process involves a lot of hurdles. Who should I see (a psychologist, a psychiatrist, a social worker, or another kind of counselor)? Who do my friends or family recommend (is it weird to ask them)? What style do they practice? And maybe the biggest—do they take my insurance?

Though not all medical providers take insurance, psychiatrists are the least likely to do so. About 55% of psychiatrists take insurance, according to a 2014 study published in JAMA Psychiatry; the average for all health care professionals is around 89%. Cardiology, oncology, and orthopedic surgery were the specialties had the highest percentage of doctors who accepted insurance.

Psychiatrists are also least likely to accept government-sponsored healthcare:

This occurs because insurance companies often complicate a therapist’s job, said Joe Parks, a senior medical advisor with the National Council for Behavioral Services.

Parks explained that therapists receive multiple offers from insurance companies to be included in their network, but these offers come at a pay rate that may be below what the therapist could charge independently. There’s no uniformity with what constitutes an hour of treatment. For some it translate into 45 minutes per session or 50 minutes with time built in for paperwork.

“The majority of office-based psychiatrists practice in solo practices which can likely function with much less infrastructure than larger single-specialty or multi-specialty group practices,” the authors of the 2014 study write. Solo practices may not have the resources (pdf, pg. 310) to accommodate extra space for administrative help, and according to the American Psychological Association, many insurance companies haven’t updated reimbursement rates for therapists in 10 or 20 years, despite rising administrative costs. As a result, Parks said, “that is why most insist the patient pay cash and deal with the insurance [company] themselves.”

If a patient’s insurance company finds a reason why it shouldn’t pay for treatment, the psychiatrist cannot bill the patient separately. The time spent seeing that patient is a sunk cost.

For all of these reasons, therapists make patients pay out of pocket. But, this means that many potential patients can’t afford treatment. In 2011, a report (pdf) from the US Department of Health and Human Services found that of the 45.6 million American adults with any kind of mental health illness, fewer than half received treatment. The most widely cited reason for not seeking treatment was that—insurance or not—patients couldn’t afford it.

Private insurance companies, Medicaid, and Medicare are required to have a certain number of therapists in their network available for clients, Parks explained. They should provide subscribers with a list of addresses and numbers for in-network therapists. “What almost never gets done is see if they���ve been updated, and if the doctor is taking anyone,” he said.

“Unfortunately, it can be a lot of work for the patients,” he said. “And when you’re going through an emotional crisis you don’t feel like calling long lists of people. You want to get your care so you’re not having crying episodes.”