US No Surprises Act (42 USC 300gg-111 to 300gg-139) and 45 CFR Part 149 149.410(b): Bill post-stabilization services out of network only when the attending physician confirms the patient can travel, valid notice and consent is obtained, the patient can receive it, and State law allows

Post-stabilization items and services at a nonparticipating facility, or from a nonparticipating provider at a participating emergency facility, escape the balance billing prohibition only when all of the following hold: the attending emergency physician or treating provider determines the patient can travel by nonmedical or nonemergency medical transport to an available participating provider or facility within a reasonable distance (binding on the facility); the notice and consent criteria of 149.420(c) to (g) are met, with the notice also listing participating providers at the facility who could furnish the services (participating facility case) or the good faith estimated charges of the nonparticipating facility and its providers (nonparticipating facility case); the patient or authorized representative is in a condition to receive the information and consent, as the physician judges; and any further State requirements are satisfied.