CPT code 61305: Cranial exploration, infratentorial approach2026 Medicare rate & RVUs

Medicare pays $1,959.96 for 61305 nationally in a facility.

Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.

What 61305 covers

61305 represents an exploratory cranial opening directed to the infratentorial compartment—the posterior fossa beneath the tentorium, including access around the cerebellum and brainstem. A neurosurgeon performs the craniotomy or craniectomy in an operating room when the operative objective is exploration rather than a defined evacuation or drainage procedure. Select the code by the compartment entered, not by the skin incision or the patient’s presenting symptom.

The operative report should identify the infratentorial target and document that exploration was the work performed. If the surgeon treats a specified hematoma or abscess, select the procedure code describing that objective instead. CMS assigns a 90-day major-surgery global period, including the day-before preoperative visit and 90 days of related postoperative care. When multiple procedures occur in one session, the highest-valued procedure is paid in full and the others at 50%. Assistant-at-surgery services may be paid; co-surgeon payment requires supporting documentation, and team surgery is not permitted. Modifier 50 is inappropriate for this code’s anatomy and descriptor.

This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.

Where 61305 pays more and less

The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.

109 of 109 payment localities

61305 rates by state

Office rate range in each state. Select a state to see its payment localities.

How the 61305 rate is calculated

Each of 61305’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.

Payment rules and modifiers for 61305

61305 has a 90-day global period: related visits in that window are included in the surgery payment.

What modifiers do to the payment

When to use modifier 51

61305 compared with similar codes

How to choose

61304Exploratory craniotomySupratentorial

Choose 61305 for exploration below the tentorium in the posterior fossa; choose 61304 for exploration above the tentorium.

61314Hematoma evacuationInfratentorial, extradural or subdural

61305 describes infratentorial exploration. Use 61314 when the operation is specifically evacuation of an infratentorial extradural or subdural hematoma.

61315Hematoma evacuationIntracerebellar, infratentorial

61305 describes exploration; 61315 applies when the surgeon evacuates an intracerebellar hematoma.

Codes related to 61305

Related codes aren’t interchangeable: bill the code that matches the service performed.

Where these rates come from

FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.

CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027

Open CMS sourceHow we calculate rates