Enacted at the end of 2020, the federal No Surprises Act (NSA) prohibits certain health care providers and facilities that provide their services outside of health plan provider networks from "balance billing." As a result, those providers and facilities cannot hold patients responsible for the difference between what the provider or facility charges and what health plans or other third-party payers pay for the services.

Recent court decisions have put the rules for determining how much health plans and insurance companies pay those out-of-network providers who are prohibited from balance billing under the new law in flux, further complicating the already complex system for paying health claims. Because providers continue to file lawsuits challenging portions of the federal regulations governing these provider payments, it is unlikely that providers or payers will have a satisfactory or predictable process in place for determining out-of-network payment rates anytime soon.

There are three types of out-of-network health care services covered by the NSA's balance billing prohibitions: emergency services, air ambulance services, and certain services provided to patients on an out-of-network basis within an in-network facility, such radiology or anesthesiology services from out-of-network providers within an in-network hospital. The NSA directs how payments to out-of-network providers rendering these services will be determined, and the U.S. Departments of Health and Human Services, Labor, and Treasury have issued regulations and related guidance for making those payment determinations.