`77520` Proton trmt simple w/o comp

What 77520 is

CMS fee schedule short descriptor: Proton trmt simple w/o comp.

Full CPT long descriptions are licensed by the American Medical Association and are not published on this site; the short descriptor above is the one CMS prints in its own fee schedule file. See About CPT.

Medicare payment for 77520 (CY2026)

This code has no Physician Fee Schedule rate: Carrier-priced - the Medicare contractor sets the price. It may be paid under a different fee schedule (clinical laboratory, DMEPOS, anesthesia) or not paid at all - check the relevant CMS schedule.

Medically Unlikely Edit (MUE)

Medicare caps 77520 at 2 units per date of service for practitioner claims (MAI 3 - date of service edit (clinical): units above the MUE may pay with documentation on appeal), rationale: Nature of Service/Procedure. Units above the cap are denied unless the edit's adjudication rules allow an appeal with documentation.

Billed with 77520? These codes are bundled into it

77520 is a Column 1 code in 220 active NCCI PTP edits. When one of these Column 2 codes is reported on the same date of service, it is denied as bundled - unless the edit's modifier indicator is 1 and documentation supports a distinct service with an NCCI-associated modifier.

Column 2 code	Short description	Modifier indicator
`0591T`	Hlth&wb coaching indiv 1st	1 - modifier may bypass	Check pair
`0592T`	Hlth&wb coaching indiv f-up	1 - modifier may bypass	Check pair
`0593T`	Hlth&wb coaching group	1 - modifier may bypass	Check pair
`0596T`	Temp fml iu vlv-pmp 1st insj	0 - no modifier bypass	Check pair
`0597T`	Temp fml iu valve-pmp rplcmt	0 - no modifier bypass	Check pair
`11920`	Correct skin color 6.0 cm/<	0 - no modifier bypass	Check pair
`11921`	Correct skn color 6.1-20.0cm	0 - no modifier bypass	Check pair
`16000`	Initial treatment of burn(s)	0 - no modifier bypass	Check pair
`16020`	Dress/debrid p-thick burn s	0 - no modifier bypass	Check pair
`16025`	Dress/debrid p-thick burn m	0 - no modifier bypass	Check pair
`16030`	Dress/debrid p-thick burn l	0 - no modifier bypass	Check pair
`36000`	Place needle in vein	1 - modifier may bypass	Check pair
`36410`	Vnpnxr 3yr/> phy/qhp dx/ther	1 - modifier may bypass	Check pair
`36425`	Venipuncture cutdown 1 yr/>	0 - no modifier bypass	Check pair
`36591`	Draw blood off venous device	0 - no modifier bypass	Check pair
`36592`	Collect blood from picc	0 - no modifier bypass	Check pair
`51701`	Insert bladder catheter	0 - no modifier bypass	Check pair
`51702`	Insert temp bladder cath	0 - no modifier bypass	Check pair
`51703`	Insert bladder cath complex	0 - no modifier bypass	Check pair
`77371`	Srs multisource	0 - no modifier bypass	Check pair
`77372`	Srs linear based	0 - no modifier bypass	Check pair
`77373`	Strtctc bdy rad ther tx dlvr	0 - no modifier bypass	Check pair
`77402`	Radiation tx delivery lvl 1	0 - no modifier bypass	Check pair
`77407`	Radiation tx delivery lvl 2	0 - no modifier bypass	Check pair
`77412`	Radiation tx delivery lvl 3	0 - no modifier bypass	Check pair
`90832`	Psytx w pt 30 minutes	0 - no modifier bypass	Check pair
`90833`	Psytx w pt w e/m 30 min	0 - no modifier bypass	Check pair
`90834`	Psytx w pt 45 minutes	0 - no modifier bypass	Check pair
`90836`	Psytx w pt w e/m 45 min	0 - no modifier bypass	Check pair
`90837`	Psytx w pt 60 minutes	0 - no modifier bypass	Check pair

Showing 30 of 220 column 2 codes. Use the pair checker for any specific combination.

77520 is bundled into these codes

77520 appears as a Column 2 code in 6 active edits. Reported with one of these Column 1 codes on the same date of service, 77520 is the code that denies.

Column 1 code	Short description	Modifier indicator
`32701`	Thorax stereo rad targetw/tx	0	Check pair
`77301`	Radiotherapy dose plan imrt	0	Check pair
`77423`	Neutron beam tx complex	0	Check pair
`77522`	Proton trmt simple w/comp	1	Check pair
`77523`	Proton trmt intermediate	1	Check pair
`77525`	Proton treatment complex	1	Check pair

Data: CMS CY2026 Physician Fee Schedule RVU file (October release, RVU26D) and Medicare NCCI PTP practitioner edits v32.3 (2026 Q4). Verify against the official files before billing or contracting decisions.