What can I do if I disagree with a medical bill?

If the No Surprises Act protects the care, you owe only your in-network share, and any dispute over the rest is between the provider and your plan, without you: under the federal law, in federal independent dispute resolution (42 U.S.C. § 300gg-111(c); 45 CFR 149.510), and where a state’s own law applies, in that state’s process. In the federal process the arbiter must consider, alongside the QPA, the provider’s level of training, experience, and quality and outcomes, and any contracted rates between that provider and the plan in the previous four plan years, and may not consider the provider’s billed charges or what Medicare or Medicaid would pay (42 U.S.C. § 300gg-111(c)(5)(C) and (D)). If you had no insurance or paid for care yourself and the bill is at least $400 over your good faith estimate, you may dispute it yourself within 120 days of the bill (42 U.S.C. § 300gg-137; 45 CFR 149.620).

CMS publishes every federal dispute line by line, naming the provider and the plan, with each offer shown only as a percentage of the plan’s QPA. The dollar amounts, the QPA among them, are in a separate file that names neither, so you can read what a doctor asked as a multiple of the QPA, but never the QPA beside the plan that set it.

What is federal IDR? — answered from the law, on provern.org