CPT code 70555: Functional brain MRI, physician or psychologist2026 Medicare rate & RVUs in California

CMS doesn’t publish an office rate for 70555 in California.

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

What 70555 covers

This service is functional MRI of the brain used to map activity associated with tasks such as language or movement. A physician or psychologist participates in the examination; the professional service includes interpretation and a report. Functional mapping is commonly used when clinicians need to identify important functional areas in relation to a planned brain procedure, including evaluations of brain lesions or seizure disorders. It is performed in hospital and imaging-center settings.

Medicare assigns status C, carrier priced: CMS publishes no national payment, and the Medicare Administrative Contractor sets payment for each claim. Report modifier 26 for the professional interpretation, modifier TC for the technical service, or neither modifier for the global service. When performed bilaterally, each side is paid separately. Code 70554 is the related technologist-performed functional brain MRI service; choose between these codes according to whether a physician or psychologist participates in the examination.

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 70555 pays more and less in California

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

29 of 29 payment localities

How the 70555 rate is calculated

Each of 70555’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 70555

The CMS indicators that decide how 70555 is paid alongside other services.

What modifiers do to the payment

When to use modifier 26

70555 compared with similar codes

How to choose

70554Functional brain MRITechnologist acquisition

Use 70555 when a physician or psychologist participates in the functional MRI examination. Use 70554 for the technologist-performed service.

70557Brain MRIWithout contrast

70557 reports structural brain MRI without contrast; 70555 reports functional brain mapping with physician or psychologist participation.

70559Functional brain MRIWithout and with contrast

70559 reports structural brain MRI without and with contrast. It is distinct from functional brain mapping reported with 70555.

Codes related to 70555

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