Your prior authorisation was denied — which appeal you actually get

Two people are refused the same infusion in the same week — one on her employer's self-funded plan, one on a Medicare Advantage plan. Both letters say "not medically necessary" and both invite an appeal. She has four months to reach an independent organisation that can overrule the plan. He has sixty days to ask for a reconsideration the plan must then hand to a federal contractor unprompted. The advice written for one is useless for the other.

The first question is not clinical. It is who regulates the plan

Establish which of four systems the denial came out of before writing anything. The card in your wallet often does not say — a self-funded employer plan and a fully insured one can carry the same insurer's logo and run on different law. The summary plan description, or a call asking whether the plan is self-funded, settles it.

"Urgent" is a legal category, and your clinician defines it

Under 29 CFR § 2560.503-1(m)(1) a claim involves urgent care where the standard timeframe could seriously jeopardise life or health, or the ability to regain maximum function, or would subject the claimant to severe pain that cannot be adequately managed without the care. Then 45 CFR § 147.136(b)(2)(ii)(B) adds the part almost nobody uses: urgency is "as determined by the attending provider, and the plan or issuer shall defer to such determination".

The practical form is a short signed note from the treating clinician, filed with the request, saying which limb of the test is met and why — not "this is urgent" but what deteriorates over the next fortnight. If the request is incomplete the plan has 24 hours to say what is missing and must allow at least 48 hours to supply it.

The denial notice owes you the rule it was decided under

A denial saying only "not medically necessary" is not a compliant notice. Under 29 CFR § 2560.503-1(g)(1)(v)(A), where an internal rule or guideline was relied on, the notice must give you the criterion or state that a copy comes free of charge on request. Under (g)(1)(v)(B), where the denial rests on medical necessity or an experimental exclusion, the plan owes an explanation of the clinical judgment "applying the terms of the plan to the claimant's medical circumstances". Paragraph (j)(5) repeats both on appeal.

Two further entitlements belong in the same letter. Paragraph (h)(2)(iii) gives you free copies of everything relevant — the claim file, not a summary. And § 147.136(b)(2)(ii)(C) requires the plan to send you, free and early enough to answer it, any new evidence or rationale it generates before a final denial. A plan that produces a fresh reason in its final letter has removed the response the regulation guarantees.

The peer-to-peer call is not the appeal

A peer-to-peer review is a conversation between the treating clinician and a reviewer for the plan. Take it when offered: a reviewer who understands the case can simply reverse. But it appears nowhere in 29 CFR § 2560.503-1 or 45 CFR § 147.136, and nothing in either regulation stops a deadline while one is being scheduled. Some states require the opportunity — Texas Insurance Code § 4201.206 makes a utilisation review agent let the treating provider discuss the case with a physician of the same or similar specialty before an adverse determination issues. That is a duty owed before the denial, not a substitute for the appeal after it, and it does not reach a self-funded ERISA plan.

What a strong appeal actually contains

Appeals that succeed treat the plan's own criterion as a checklist and answer it element by element. Most appeals instead argue that the treatment is a good idea, which is not the question in front of the reviewer. The reviewer asks whether documented facts satisfy a written standard, and every element left unaddressed is one the plan gets to call unmet.

The expedited sequence, in the order the regulation forces

1. 1

   Get the attending provider to call it urgent, in writing

   Everything below turns on this. Section 147.136(b)(2)(ii)(B) makes the attending provider's judgement the test and requires the plan to defer to it. Without it the same claim runs on 15-day and 30-day clocks.

2. 2

   Demand the criterion and the claim file the same day

   Under 29 CFR § 2560.503-1(h)(2)(iii) copies of everything relevant come free on request. Send the demand with the appeal, so the clock runs while the documents travel.

3. 3

   File the expedited internal appeal

   It may be made orally. The decision is due as soon as the medical exigencies require and no later than 72 hours after the plan receives the request.

4. 4

   Ask for expedited external review at the same time

   Section 147.136(d)(3)(i)(A) allows the request at the point of the first denial, provided an expedited internal appeal has been filed. The IRO must then decide within 72 hours of receiving the case.

5. 5

   Send your evidence straight to the review organisation

   Its eligibility notice must tell you that you may submit more within ten business days, and it must consider what arrives in that window. It reviews the claim de novo, bound by nothing the plan concluded.

Medicare Advantage sends the appeal onward for you

Part C runs on its own vocabulary: the initial decision is an organisation determination and the appeal a reconsideration. The feature no commercial plan has sits at 42 CFR § 422.592 — where the plan affirms its denial in whole or in part, the case must go to an independent entity contracted by CMS, and the plan sends it. Nothing is required of the enrollee at that stage.

Two Part C rules are worth knowing before a denial arrives. A medical necessity denial must be reviewed by a physician or other appropriate professional with expertise for the service before the plan issues it — § 422.566(d). And under § 422.138(c), once a plan has approved an item through prior authorisation it may not later deny coverage for lack of medical necessity, nor reopen the approval except for good cause or reliable evidence of fraud.

Original Medicare, and Medicaid, work nothing like either

Traditional Medicare has historically had almost no prior authorisation, and where it exists the decision is not appealable. That changed at the edges on 1 January 2026, when the WISeR model began applying prior authorisation or pre-payment review to a set of outpatient services — skin substitutes, certain orthopaedic pain procedures, nerve stimulator implants — in six states, running to the end of 2031. Even there, an unfavourable decision becomes appealable only once the service is furnished and the resulting claim denied, at which point the ordinary Medicare appeal opens with a redetermination inside 120 days.

Medicaid managed care is the opposite shape: compressed, with a state official at the end. A plan may have only one level of appeal. The enrollee has 60 calendar days from the date on the notice to file, the plan has 30 calendar days to resolve it or 72 hours expedited, and a fair hearing can then be requested within a window each state sets between 90 and 120 days. If the plan misses its own notice or timing rules the appeal is deemed exhausted and the enrollee goes straight to the hearing.

What actually changed on 1 January 2026

The CMS Interoperability and Prior Authorization final rule, CMS-0057-F, is widely described as putting every insurer on a 72-hour and seven-day clock. It does not. Its reach is Medicare Advantage organisations, state Medicaid and CHIP fee-for-service programmes, Medicaid and CHIP managed care plans, and qualified health plan issuers on the federally facilitated exchanges. Employer group health plans are outside it, and drugs are excluded throughout.

• The decision clocks are real but not universal. From 1 January 2026 an MA organisation and a state Medicaid programme each have 7 calendar days for a standard prior authorisation decision and 72 hours expedited. The marketplace rule at 45 CFR § 156.223 sets no decision timeframe at all; those plans already run on the 15-day and 72-hour claims clocks.
• Every impacted payer must give a specific reason for a denial from 1 January 2026, and must publish by 31 March each year its approval and denial rates and the percentage of denials approved after appeal.
• The APIs are 2027, for plan years beginning on or after 1 January.

Separately, from 1 January 2026 a large group of insurers took on voluntary commitments announced with HHS and CMS in June 2025 — narrowing the scope of prior authorisation, and honouring an existing authorisation for a 90-day transition when a patient changes plans. Worth citing on the phone; not law, and carrying no enforceable deadline.

The number that should change how you behave

KFF's analysis of federal transparency data for HealthCare.gov plans found roughly 85 million in-network claims denied in 2024, a denial rate near 19%, against fewer than 263,000 consumer appeals — under 1%. Insurers upheld 66% of the internal appeals they did receive, and around 5,881 external appeals were filed. The pipeline narrows by two orders of magnitude before it reaches the one reviewer who does not work for the plan.

That is not an argument that appeals are futile; it is the opposite. The stage with an independent decider, a de novo standard and no cost to you is the stage almost nobody reaches, and what stands between most people and it is a criterion they never asked for and a deadline nobody wrote down. Get the rule the denial was decided under. Get the clinician to say the word urgent, if it is true. Then put the dates in a deadline tracker the day the letter arrives — the discipline that also decides a good-faith estimate dispute or an observation status challenge. If you are appealing for a relative, sort the medical authorisation and the records release first: the plan will not speak to you without them, and the 72 hours will not wait.