“Balance bills” primarily occur in two circumstances: 1) when an enrollee receives emergency care either at an out-of-network facility or from an out-of-network provider, or 2) when an enrollee receives elective nonemergency care at an in-network facility but is inadvertently treated by an out-of-network health care provider. Since the insurer does not have a contract with the out-of-network facility or provider, it may decide not to pay the entirety of the bill. In that case, the out-of-network facility or provider may then bill the enrollee for the balance of the bill. While 33 states have enacted laws to protect enrollees from balance billing, the scope of these protections varies as shown in the map below. Congress enacted the No Surprises Act in 2020 to protect most people who are not currently protected under this patchwork of state laws. This federal law goes into effect on January 1, 2022.
See here for the criteria used to determine which states have comprehensive or partial protections.