You had chest pain at 2 AM and went to the emergency room. The ER ran tests — everything turned out to be fine. Then your insurance company sends a denial letter: "This emergency visit is not covered because the final diagnosis was not a medical emergency." This is one of the most infuriating denials patients face. It is also, in most cases, illegal under federal and state law. Here is how to fight it.
The Prudent Layperson Standard: Your Legal Shield
The "prudent layperson" standard is the legal foundation of every ER denial appeal. It requires insurers to evaluate emergency claims based on what a person with average medical knowledge would have reasonably considered an emergency given the symptoms at the time — not the final diagnosis. This standard is established by:
- The Affordable Care Act (ACA): Requires all non-grandfathered plans to cover emergency services without prior authorization and without applying higher cost-sharing than in-network
- EMTALA (Emergency Medical Treatment and Labor Act): Requires hospitals to provide stabilizing emergency care regardless of insurance
- Most state laws: Over 40 states have enacted their own prudent layperson standard statutes
- Medicare and Medicaid: Both programs apply the prudent layperson standard
What symptoms are clearly "emergencies"
The following symptoms clearly qualify as emergencies under any reasonable prudent layperson standard: chest pain or pressure, difficulty breathing, severe abdominal pain, sudden severe headache, high fever (especially in children), signs of stroke (sudden weakness, speech problems, facial drooping), severe allergic reactions, uncontrolled bleeding, loss of consciousness, and sudden severe back pain. Even if the final diagnosis is benign, the symptoms themselves warranted ER evaluation.
Step 1: Get the Full Denial in Writing
If you received a verbal denial or a denial notice without complete explanation, request the full written denial. It must state:
- The specific clinical or contractual basis for the denial
- The criteria used to evaluate the claim
- Your right to appeal and the appeal deadline
- How to request a copy of the review criteria
Step 2: Get Your ER Medical Records
Request your complete ER records from the hospital's medical records department. You're entitled to these under HIPAA. Your records will show:
- Your presenting complaints and chief symptoms as you described them
- Vital signs at arrival (elevated heart rate, high blood pressure, fever, etc.)
- The triage assessment (your acuity level)
- Tests ordered and their clinical rationale
- The treating physician's assessment and reasoning
The presenting symptoms and triage documentation are the most important evidence in an ER denial appeal. They show what the situation looked like at the time — before diagnosis.
Step 3: Write Your Appeal Letter
Your appeal letter should:
- State the legal basis: Cite the ACA prudent layperson standard and any applicable state law
- Describe your symptoms at the time: Be specific — "sudden onset chest pain radiating to my left arm, shortness of breath, and dizziness" is more compelling than "chest pain"
- Reference the medical records: Quote or attach the relevant portions showing triage acuity and presenting symptoms
- Explain why a reasonable person would have gone to the ER: Make the argument explicitly — what would any reasonable person have done with those symptoms at that time?
- Request the treating physician's letter: An ER physician's statement that the visit was appropriate given the presenting symptoms is extremely powerful
No Surprises Act: OON ER Protections
Under the No Surprises Act, effective January 2022:
- Insurers must cover emergency care at any emergency department, in-network or out-of-network
- Your cost-sharing cannot exceed what it would be for the same service at an in-network facility
- OON ER providers cannot balance-bill you
- No prior authorization can be required for emergency services
If you received a bill for emergency care at an out-of-network ER, or if your insurer applied out-of-network cost-sharing, this may be a No Surprises Act violation. See our out-of-network appeal guide for details on how to dispute this.
Observation Status: A Hidden ER Issue
Some patients who come to the ER and are kept overnight are placed in "observation status" rather than formally admitted as inpatients. This distinction has major cost implications:
- Observation patients are technically outpatients, not inpatients
- Medicare Part A does not cover observation stays — they're covered under Part B with different cost-sharing
- A three-day qualifying inpatient hospital stay (required for Medicare skilled nursing facility coverage) does NOT include observation days
If you were in the hospital overnight and weren't told about observation status, ask the hospital to review and potentially reclassify your status. You can also appeal through the MOON (Medicare Outpatient Observation Notice) process. A patient advocate can be critical in navigating this — see our patient advocate guide.
Filing Your Internal Appeal
Submit your appeal with:
- Your appeal letter citing the prudent layperson standard
- Copies of your ER medical records (or the most relevant sections)
- A letter from the treating ER physician if available
- Any applicable state prudent layperson statute citations
- Your EOB showing the denial
If the internal appeal is denied, request external review immediately. ER denial external review cases have strong overturn rates because external reviewers must apply the prudent layperson standard — not the insurer's internal criteria.
For help writing your appeal, use our free appeal letter generator. For a thorough understanding of what drives appeal success, read our appeal success rates guide.
Sources: ACA Section 2719A (emergency services) · No Surprises Act · EMTALA · State prudent layperson statutes. Disclaimer: This article is for informational purposes only. Emergency care coverage rules vary by plan type and state. Last updated: March 2026.