Prior Authorization Services

Which services usually need prior authorization

The list is longer than most schedulers expect and it differs by payer. Advanced imaging almost always needs it under commercial and Medicare Advantage plans: MRI of the brain (70553), MRI of the lumbar spine (72148), CT and PET. Injections and infusions billed under J codes need it and often need the drug and the administration approved separately, so infliximab (J1745) and the infusion code (96413) can be approved as a pair. Interventional pain procedures such as transforaminal epidural injections (64483) are usually reviewed against step therapy criteria. Surgical and in-office procedures, sleep studies, DME above a dollar threshold, and physical therapy beyond an initial visit count are common. Behavioral health sessions are frequently authorized in blocks, and the block runs out quietly. We build a payer-by-payer matrix for your top CPT codes so scheduling knows at booking, not at check-in, whether an auth is required.

How we obtain and track them

Every request starts with a check of the payer portal, or a 278 transaction where the payer supports it through your clearinghouse. Where a payer routes imaging through a radiology benefit manager such as eviCore or Carelon, we submit there and follow that vendor's clinical criteria. Where the portal fails or the case is urgent, we call, and we log the reference number, the representative name and the time. The request carries the ordering and rendering NPIs, the site of service, the ICD-10 codes that support medical necessity and the specific clinical notes the payer's policy asks for, because a request missing one of those pends rather than approving. Every request sits in a single log with a status, a next action and an owner until it is approved, denied or withdrawn.

What the payer owes you, and when

Turnaround is no longer purely at the payer's discretion. Under the CMS Interoperability and Prior Authorization Final Rule, Medicare Advantage plans, Medicaid and CHIP programs and marketplace plans must decide urgent requests within 72 hours and standard requests within seven calendar days starting January 1, 2026, and they must state a specific reason for any denial. Medicare Advantage organization determinations were already bound by 42 CFR 422.568. Commercial plans regulated by states have their own limits, often 15 days for standard requests. We track each request against the deadline that applies to that payer, and a request that goes past it is escalated with a reference to the rule rather than left in a queue.

The CO-197 and CO-15 denial pattern

CO-197 is the payer saying no authorization was on file. CO-15 is the payer saying the authorization number on the claim is missing or invalid. A CO-15 is often a clerical fix: the auth exists and the number was mistyped, left off, or attached to the wrong line. A CO-197 means the service was performed without approval, and the only path is a retro-authorization request, which most payers allow only within a short window, often 2 to 14 days, and only for specific reasons like emergency or a coverage change the practice could not have known about. We work both within 48 hours of posting because the retro window is the shortest deadline in billing. Where a payer denies for authorization but an approval was in fact issued, denial management appeals with the approval letter and the call reference.

Matching what was authorized to what was performed

An authorization is for a specific CPT, a specific number of units, a date range, and often a specific site of service and rendering NPI. The claim has to match all of them. The most common miss is a procedure that changed in the room: an MRI authorized without contrast performed with contrast, an epidural authorized for one level given at two, or a therapy plan authorized for eight visits that ran to ten. Before each claim goes out we compare the billed CPT and units against the authorization on file. If they differ, we hold the claim and request a modification or an added unit before submitting, because a mismatched claim denies and a denied claim on a modified service is hard to recover.

The auth calendar for expiring authorizations

Authorizations expire, and blocks of visits run out, and both happen without a warning from the payer. We keep an auth calendar for every active authorization in your practice showing the end date, the units used against the units approved, and the renewal lead time the payer requires. Fourteen days before an auth expires, or when three quarters of approved units are used, the renewal request goes out with the updated clinical notes. For behavioral health and physical therapy, where a patient may be seen weekly for months, this is the difference between continuous coverage and a gap of unpaid sessions the patient did not know they would owe. Scheduling sees the calendar too, so an appointment is never booked past an expired auth.

What you get

Every morning your front desk receives a daily auth status log listing each pending request, its payer, its reference number, its status and the next step. Alongside it come pre-visit alerts for the next three business days: any scheduled visit where an auth is required and not yet approved is flagged, with a recommendation to hold, reschedule or proceed with an ABN or self-pay conversation. You get a monthly summary of requests submitted, approved, denied and appealed by payer, with turnaround times against the deadline that applies, so you can see which payers are slow and which CPT codes are being denied on medical necessity.