How many prior authorizations are denied?

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Insurers deny between 12% and 18% of standard prior authorization requests across major health coverage types.

Recent data from the Kaiser Family Foundation (KFF) shows how denial rates break down by insurance category:

Denial Rates by Insurance Type

  • Medicare Advantage: About 12% of requests are denied (rates range from 5% to 17% depending on the company).
  • Medicaid Managed Care: About 14% of requests are denied (rates range from 2% to 23%).
  • ACA Marketplace Plans: About 18% of requests are denied (rates range from 3% to 25%).

Total Numbers and Volume

  • In 2024, Medicare Advantage Insurers received nearly 53 million requests and fully or partially denied 4.1 million of them (about 7.7% of total volume for that specific year).
  • Traditional Medicare had a higher percentage denial rate on fewer total requests, denying roughly 22.9% of its smaller pool of reviews.

What Happens on Appeal?

  • Low appeal rates: Only a small percentage of patients or doctors appeal these denials (often around 11% to 12%).
  • High overturn rates: When people do appeal, insurers overturn a large portion of their original denials—reversing roughly 43% to 67% of appealed cases.

Do most prior authorizations get approved?

Yes, most prior authorizations do get approved by health insurance companies, with overall approval rates typically ranging between 85% and 95% depending on the plan and service.

Approval and Denial Rates

  • High Approval Rates: Major insurers like UnitedHealthcare report that over 90% of required prior authorization requests are ultimately approved. Reported averages hover around 80% to 95% across different public and private markets.
  • Initial Denials: Despite high final approval rates, roughly 10% to 25% of requests are initially denied or flagged for needing more information or alternative step-therapy.
  • Appeals Success: When an initial request is denied, formal appeals submitted by healthcare providers successfully overturn a large majority—often around 80%—of those denials.

Why the Process Still Causes Friction

  • Delays and Burden: Even though most requests are approved, the administrative wait times can stall patient care for days or weeks.
  • Deterrence Effect: The requirement itself often discourages doctors or patients from submitting requests for costly treatments in the first place, which keeps overall submission numbers lower.
  • For a deeper look at the data and regulations surrounding these metrics, review the KFF Quick Takes report.

Do prior authorizations get denied?

Yes, prior authorizations do get denied by health insurance companies.

Denial rates typically range from 2% to 25% depending on the insurer and plan type (such as Medicare Advantage or ACA Marketplaces), averaging around 12% to 18% overall.

Common Reasons for Denials

  • Missing or incomplete documentation: Clinical notes, test results, or medical history required by the insurer are absent.
  • Lack of medical necessity: The insurer decides the treatment is not fully justified based on their guidelines.
  • Step therapy not met: The patient has not tried and failed a cheaper, required alternative first.
  • Service not covered: The requested drug or procedure is excluded under the specific policy.
  • Administrative errors: Incorrect billing codes or missing patient information are submitted.

What to Do If Denied

  • Review the denial letter: Find the exact reason for the rejection and any instructions or deadlines for an appeal.
  • Partner with your doctor: Ask your physician's office to supply missing clinical notes, lab results, or a letter of medical necessity.
  • File an appeal: A large portion of initial prior authorization denials are overturned when extra documentation is provided during the appeal process.

What is a common reason for a prior authorization required rejection?

A common reason for a prior authorization rejection is missing or incomplete clinical documentation. Insurance companies often reject requests because they lack required lab results, imaging reports, or clinical notes.

Other Common Reasons

  • Lack of Medical Necessity: The submitted details do not prove the treatment or medication meets the payer's clinical guidelines.
  • Coding Errors: The CPT (procedure) or ICD-10 (diagnosis) codes are wrong or do not match.
  • Step Therapy Requirements Not Met: The patient did not try or fail lower-cost, preferred alternative treatments first.
  • Non-Formulary Drugs: The requested medication is not on the insurance plan's approved drug list.

What healthcare has the highest denial rate?

Oscar Health has the highest claim denial rate among major Affordable Care Act (ACA) marketplace health insurers, denying approximately 25% of in-network claims.

Denial rates vary depending on whether you look at insurance companies, government programs, or medical specialties.

Highest Denial Rates by Insurance Company (ACA Marketplace)

  • Oscar Health: ~25% denial rate
  • Molina Healthcare: ~22% denial rate
  • GuideWell (Florida Blue): ~22% denial rate
  • Cigna & BCBS of Tennessee: ~21% denial rate each

Highest Denial Rates by Medicare Advantage

  • UnitedHealth Group: Leads major insurers with a roughly 17% denial rate on standard prior authorization requests.
  • Aetna and Centene: Follow closely with high prior authorization denial rates in government-backed plans.

Highest Denial Rates by Medical Specialty

  • Neurology: Frequently reports the highest initial professional claim and service denial rates (ranging from 20% to 35%) due to strict medical necessity and documentation rules.
  • Cardiology: Encounters high denial rates (12% to 20%) because of complex diagnostic bundling and prior authorization requirements.
  • Orthopedics: Faces high initial denial and rejection rates (10% to 18%) largely tied to outpatient surgical and procedural pre-approvals.

Understanding Prior Authorization

9 related questions found

What percent of prior authorizations are denied?

On average, health insurers deny between 12% and 18% of standard prior authorization requests.

Recent health data from KFF Analysis on Prior Authorization Metrics breaks down standard denial rates by insurance market:

  • ACA Marketplace plans: 18% denied (ranging from 3% to 25% depending on the insurer).
  • Medicaid managed care: 14% denied (ranging from 2% to 23%).
  • Medicare Advantage: 12% denied on standard requests (ranging from 5% to 17%), though general volume-based calculations can vary depending on partial versus full denials.

Appeals and Overturns

  • Low appeal rates: Only about 11% of denied requests are formally appealed by providers or patients.
  • High overturn rates: When an appeal does happen, a large percentage of denials are overturned—67% in Medicare Advantage, 47% in Medicaid, and 43% in ACA Marketplaces.

How long do prior authorizations take to get approved?

Prior authorizations typically take anywhere from 24 hours to 14 business days to get approved, depending on the urgency and the type of request.

⏱️ Approval Timelines by Request Type

  • ⚡ Urgent/Expedited requests: 24 to 72 hours (for serious or life-threatening conditions).
  • 💊 Standard prescription drugs: 24 to 72 hours (up to 1–3 business days).
  • 📋 Standard medical services or imaging: 3 to 14 business days.
  • 🏥 Complex or specialty treatments: 2 to 4 weeks (if extra clinical review is needed).

⚠️ Common Causes of Delay

  • Incomplete paperwork: Missing medical codes, chart notes, or provider signatures.
  • Submission method: Older paper fax or mail workflows instead of electronic prior authorization (ePA).
  • Payer backlogs: High volume of requests at the insurance company.

💡 How to Speed Up the Process

  • Ask for urgent status: Have your doctor flag the request as expedited if a delay threatens your health.
  • Follow up daily: Call your insurance company's member services line or your doctor's office to confirm receipt of all documents.
  • Use electronic portals: Verify that your provider is submitting the request electronically for real-time tracking.

On forums like Reddit, opinions on timelines are mixed: some patients see approvals in under 24 hours, while others face weeks of delays due to missing information or administrative errors.

How do I fight a denied prior authorization?

You can fight a denied prior authorization by reading your denial letter, requesting a peer-to-peer review with your doctor, and filing a formal appeal. For more insights and advocacy resources, you can visit Fix Prior Auth or review common hurdles through CoverMyMeds.

Steps to Fight the Denial

  • Read the denial letter: Find the exact reason code, the clinical criteria cited, and your specific appeal deadline.
  • Call your insurer: Ask for the specific clinical policy bulletin used to deny your care and note the representative's name.
  • Request a peer-to-peer review: Have your doctor call the insurance company's medical director to explain your clinical need directly.
  • Gather documentation: Collect medical records, clinical notes, and supporting research or CPT codes that prove medical necessity.
  • File a formal appeal: Submit a written appeal letter before your plan's deadline, and request an expedited 72-hour review if your health is at immediate risk.

Why do doctors hate prior authorization?

Doctors dislike prior authorization because it creates heavy administrative work, delays patient care, and undermines their clinical judgment.

Heavy Administrative Burden

  • Wasted time: Doctors and their staff spend roughly 12 to 16 hours every week filling out forms, faxing documents, and waiting on hold.
  • Burnout: Managing dozens of authorization requests per doctor each week contributes significantly to staff fatigue and physician burnout.
  • Frustrating reviews: The "peer-to-peer" appeals often require doctors to justify clear medical decisions to non-physicians or reviewers outside their specific medical specialty.

Harm to Patients

  • Care delays: Over 90% of physicians report that the approval process delays necessary medical treatment or prescription refills.
  • Adverse health events: Surveys by the American Medical Association show that one-third of doctors report prior authorization leading to serious medical outcomes like hospitalizations or permanent disability.
  • Treatment abandonment: Many patients give up and stop trying to get care when facing complicated insurance roadblocks.

Distrust of Insurance Motives

  • Second-guessing expertise: The process requires doctors to get a third-party corporate insurer's permission to practice medicine they already trained years to perform.
  • Cost-cutting focus: Clinicians feel the system is designed primarily to boost insurance company profits by blocking or delaying costly treatments rather than improving health.

What is the most common reason for an authorization denial?

Incomplete or missing clinical documentation is the single most common reason for a prior authorization (PA) denial across nearly every health insurance payer.

Why Documentation Fails

  • Missing chart notes: The submitted medical records lack the specific clinical notes, lab results, or imaging reports required by the insurance company.
  • Unproven medical necessity: The paperwork does not clearly show why the patient needs the specific treatment based on the payer's clinical criteria.
  • Omitted treatment history: The file fails to show that the patient tried and failed required lower-cost treatments first, known as step therapy.

Other Common Causes

  • Clerical and coding errors: Misspelled names, wrong birth dates, or incorrect CPT (Current Procedural Terminology) and ICD-10 diagnostic codes.
  • Expired windows: The approved authorization period ended before the procedure or prescription took place.
  • Non-formulary medications: The requested drug is not covered or requires a specific formulary exception.