Authorization (Prior Auth)
Pre-approval from a payer before a medical service is provided. Without it, claims are typically denied.
Authorization (Prior Auth) Explained
Prior authorization (often called pre-authorization or pre-cert) is the payer's required approval before certain medical services are performed. Approximately 15% of all claim denials trace to missing or expired prior authorization (CARC CO-15). Common services requiring prior auth include advanced imaging (MRI, CT, PET), most outpatient surgeries, durable medical equipment, specialty drugs, behavioral health beyond initial visits, and many in-office procedures depending on the payer. Each payer publishes a prior-auth list of CPT codes that varies dramatically: UnitedHealthcare requires auth for nearly all advanced imaging, Aetna for outpatient surgery, Cigna has tightened requirements aggressively since 2023, and BCBS plans vary by state. The prior-auth workflow is: identify the trigger CPT during scheduling, gather clinical documentation supporting medical necessity, submit through the payer's portal or fax form, track the response (typically 1-14 days), document the approval number on the claim, and follow up if the response window expires. Failure at any step generates a CO-15 denial that is rarely overturned post-service. Retroactive authorization is possible only in specific circumstances such as emergencies and most payers have strict deadlines (usually 24-72 hours after service) for retro-auth requests. A robust prior-auth tracking system with payer-specific rules is the single highest-leverage prevention investment for practices with imaging, surgical, or specialty-drug volume.
Related service: Authorization (Prior Auth)
Go Medical Billing handles authorization (prior auth) as a core part of our outsourced revenue cycle service. AAPC-certified team, 2.49% of collections, all 50 states.
See Also: Related Concepts
Denial
A claim that a payer refuses to pay. Common reasons: eligibility issues, missing authorization, coding errors. Each denial costs $25-$30 to rework.
Medical Necessity
The standard payers use to determine if a service is clinically appropriate. Claims can be denied for lack of medical necessity even when correctly coded.
Retroactive Authorization
Authorization obtained after a service has already been performed. Only granted under specific circumstances such as emergencies. Most payers have strict deadlines for retroactive auth requests.
Eligibility Verification
Confirming a patient's insurance coverage, benefits, deductibles, and copays before the date of service.
Where Authorization (Prior Auth) Comes Up in Practice
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