US No Surprises Act (42 USC 300gg-111 to 300gg-139) and 45 CFR Part 149 149.410(d)-(e): Retain emergency notice and consent documents for 7 years and tell the plan on each bill whether the post-stabilization conditions were met

A nonparticipating emergency facility that obtains a written consent under 149.420(e) (for itself or its nonparticipating providers) must keep the notice and consent for at least 7 years after the item or service date; a provider that obtains the consent must either arrange for the facility to retain it or keep it for 7 years itself. When billing a plan or issuer for post-stabilization items and services the provider or facility must state, on the bill or separately, whether all the 149.410(b) conditions were met for each item and service, and where applicable send a copy of the signed notice and consent.