CPT code 77318: Brachytherapy plan, complex isodose plan2026 Medicare rate & RVUs

Medicare pays $462.94 for 77318 nationally in the office. Local office rates run $408.81–$630.42.

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

What 77318 covers

A radiation oncologist directs this planning service, with a medical physicist or dosimetrist typically developing the dose distribution. The work maps the brachytherapy source arrangement—such as sources placed through an interstitial implant or an intracavitary applicator—and evaluates how dose covers the target while limiting exposure to nearby tissues. It may support temporary or permanent implant treatment in settings such as a radiation oncology department or hospital.

Choose the complex level when the documented source arrangement and planning work meet the CPT criteria for complex brachytherapy planning; the treatment site alone does not determine the level. Keep the plan and supporting dose-distribution documentation in the record, including relevant source or applicator geometry and the prescription being planned. CMS recognizes professional and technical components: report modifier 26 for the interpretation, TC for equipment and staff, or neither modifier when billing the global service.

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 77318 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

77318 rates by state

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

How the 77318 rate is calculated

Each of 77318’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 77318

The CMS indicators that decide how 77318 is paid alongside other services.

What modifiers do to the payment

When to use modifier 26

77318 compared with similar codes

How to choose

77316Brachytherapy planSimple source or point count

Use 77316 for brachytherapy planning at the simple level. 77318 requires documentation supporting complex-level planning.

77317Brachytherapy planIntermediate complexity

Both codes plan brachytherapy dose distribution; 77317 is the intermediate level, while 77318 is the complex level.

77307Isodose planningComplex teletherapy plan

77307 describes a complex teletherapy isodose plan. 77318 plans dose distribution for brachytherapy sources or applicators.

77300Dosimetry calculationBasic, per calculation

77300 is a basic radiation dosimetry calculation, not the complex brachytherapy source-distribution plan represented by 77318.

Codes related to 77318

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