Billing code 35501: Carotid bypassMedicare rate & RVUs in Illinois
Reports an autogenous vein bypass between carotid artery segments on the same side to route blood around a diseased, injured, or obstructed segment.
CMS doesn’t publish an office rate for 35501 in Illinois.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
On this page 9 sections
What 35501 covers
A vascular surgeon uses a vein graft to create a new blood-flow route between carotid artery segments on the same side of the neck. The operation may be considered when disease, injury, or another lesion prevents adequate flow through the native carotid segment. It is generally performed in a hospital operating room. The operative report should identify the side, the carotid segments joined, the graft material, and the reason for bypass.
Report this code for the ipsilateral carotid-to-carotid configuration; a bypass connecting different named arteries or the opposite carotid side is represented by a different code. If a vein is separately harvested for the graft, review the applicable harvest code and documentation. Medicare assigns a 90-day global period, including the day-before preoperative visit and related postoperative care during that period. When multiple procedures are performed in the same session, the highest-valued procedure is paid in full and other procedures are subject to the standard 50% multiple-procedure reduction. Bilateral reporting with modifier 50 is paid at 150%. An assistant at surgery may be paid; co-surgeon payment requires supporting documentation, and team surgery is not permitted.
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 35501 pays more and less in Illinois
The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.
| Payment locality | Office | Facility |
|---|---|---|
| Chicago | Unavailable | $1,648.36 |
| East St. Louis | Unavailable | $1,561.92 |
| Rest Of Illinois | Unavailable | $1,451.60 |
| Suburban Chicago | Unavailable | $1,524.56 |
How the 35501 rate is calculated
Each of 35501’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.
How the rate is built · 35501
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 28.36Practice expense 4.11Malpractice 7.26
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 35501
35501 has a 90-day global period: related visits in that window are included in the surgery payment.
CMS payment indicators · 35501
Carotid bypass
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 090 | Major surgery: the day before, the day of, and 90 days after are included. |
| Multiple procedures | 2 | Standard reduction: highest-valued procedure at 100%, others at 50%. |
| Bilateral (modifier 50) | 1 | Bilateral with modifier 50 pays 150% of the fee schedule amount. |
| Assistant at surgery (80/81/82/AS) | 2 | Paid. |
| Co-surgeons (62) | 1 | Permitted with supporting documentation. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
| Split (54/55/56) | 0.09/0.84/0.07 | Share of the payment for pre-op, the procedure itself, and post-op care. |
Global surgery period · 35501
Carotid bypass
90-day global period ends
Dec 30, 2026
Covers Sep 30, 2026 through Dec 30, 2026 (92 days, including the day before surgery).
Visit on Oct 31, 2026
Day 30 of the 90-day post-op period: related follow-up care is included in the surgical payment.
Pre-op dayGlobal period
What modifiers do to the payment
Modifier 50 · payment effect
With and without the modifier
35501 without 50 · national facility
$1,327.02
Carotid bypass
35501-50 · Bilateral: 150%
$1,990.53
Both sides on one line with modifier 50 are paid at 150% of the fee schedule amount (subject to multiple-procedure rules with other procedures).
35501 compared with similar codes
Compare codes
35501 vs 35509 vs 35506 vs 35508: national Medicare rates
Swap in your local Medicare rate.
How to choose
- 35509Carotid bypass
- Choose 35501 for a carotid-to-carotid bypass on the same side; 35509 identifies the contralateral carotid configuration.
- 35506Arterial bypass
- 35506 is for a subclavian-to-carotid bypass. This code is for a bypass between carotid artery segments on the same side.
- 35508Arterial bypass
- 35508 connects a carotid artery to a vertebral artery. Use this code for the ipsilateral carotid-to-carotid route.
35501 billing questions
How does this differ from 35509?
35501 is for a carotid-to-carotid bypass on the same side. 35509 describes a bypass between the right and left carotid arteries.
What details should the operative report support?
Document the bypass indication, laterality, carotid segments connected, and use of a vein graft. These details distinguish the ipsilateral configuration from other carotid bypass routes.
Can the vein harvest be reported separately?
When a vein is separately harvested for the bypass, review 35500 for the harvest and document the work performed. The bypass code describes the carotid reconstruction.
How is bilateral performance reported?
When the procedure is performed bilaterally, modifier 50 applies under the CMS bilateral rule; payment is at 150%. The operative documentation should establish both sides.
What postoperative care is included?
The 90-day global period includes the day-before preoperative visit and related postoperative care during the 90 days after surgery.
Can an assistant or co-surgeon be paid?
Assistant-at-surgery payment may be made. Co-surgeon payment requires supporting documentation; team surgery is not permitted.
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
Show the CMS file lines behind this rate
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