Prior Authorization in Medical Billing

Authorization is not universal

Requirements vary by payer, plan, service, place of service, and provider. Eligibility verification and authorization verification are separate tasks.

Match approval to claim

Compare authorization number, patient, provider or facility, approved service, date range, units or visits, and any conditions.

Changes can invalidate assumptions

If the treatment plan, procedure, provider, location, or date changes, determine whether the authorization remains applicable.

Keep evidence

Retain the authorization request, response, reference number, and supporting communications with the claim record.

Authorization control

• Match the authorization to the patient, provider, service, dates, quantity, and location when those elements are part of the approval.
• Do not treat authorization as a guarantee of payment; eligibility, coverage, coding, documentation, and other rules still apply.
• If the service plan changes, confirm whether an updated authorization is required.

Authorization, eligibility, coverage, and payment are different checks

Prior authorization addresses a payer’s approval process for specified services; it does not replace eligibility verification, coding, medical-necessity documentation, or other coverage/payment rules. Keep the authorization record specific enough that staff can match it to the service later. If the provider, location, date range, procedure, or quantity changes, treat that as a reason to verify the approval again rather than assuming the original number still applies.

Where to verify the rule

Requirements connected with prior authorization in medical billing can vary by payer, plan, contract, program, and date of service. Verify the rule in the payer’s current provider manual, portal guidance, or other authoritative instructions rather than treating a prior claim as the rule.

Related guides

• Backing Up Medical Billing Data
• A Beginner’s Guide to Medical Billing
• Medical Billing Modifiers: A Practical Introduction