Billing code 43644: Gastric bypassMedicare rate & RVUs in Illinois
Reports laparoscopic bariatric surgery that creates a small stomach pouch and routes it to the small intestine through a Roux-en-Y connection.
CMS doesn’t publish an office rate for 43644 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 43644 covers
A bariatric surgeon performs this operation laparoscopically to create a small stomach pouch and connect it to the small intestine in a Roux-en-Y configuration. The reconstruction changes the route food takes through the stomach and intestine. It is commonly performed in a hospital for patients undergoing surgical treatment of obesity. The operative report should describe the laparoscopic approach and the pouch and intestinal connections created.
Report the code for the completed laparoscopic Roux-en-Y operation, rather than separately coding its component steps. Medicare assigns a 90-day global period, including the day-before preoperative visit and 90 days of related postoperative care. When multiple procedures are performed in the same session, Medicare pays the highest-valued procedure in full and reduces other procedures to 50%. Modifier 50 is inappropriate for this single digestive-tract reconstruction. An assistant at surgery may be paid; co-surgeons are paid only with 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 43644 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 | $1,957.47 |
| East St. Louis | Unavailable | $1,844.59 |
| Rest Of Illinois | Unavailable | $1,726.66 |
| Suburban Chicago | Unavailable | $1,832.93 |
How the 43644 rate is calculated
Each of 43644’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 · 43644
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 28.67Practice expense 12.14Malpractice 7.64
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 43644
43644 has a 90-day global period: related visits in that window are included in the surgery payment.
CMS payment indicators · 43644
Gastric 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) | 0 | The 150% bilateral adjustment doesn’t apply. |
| 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) | 0.09/0.81/0.10 | Share of the payment for pre-op, the procedure itself, and post-op care. |
Global surgery period · 43644
Gastric 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 51 · payment effect
With and without the modifier
43644 without 51 · national facility
$1,618.27
Gastric bypass
43644-51 · Second procedure: 50%
$809.14
When this isn’t the highest-valued procedure in the session, Medicare pays 50% of its fee schedule amount (the highest is paid at 100%).
43644 compared with similar codes
Compare codes
43644 vs 43645 vs 43846 vs 43775: national Medicare rates
Swap in your local Medicare rate.
How to choose
- 43645Gastric bypass
- Use 43644 for the laparoscopic Roux-en-Y bypass; 43645 describes bypass with small-intestine reconstruction intended to limit absorption.
- 43846Gastric bypass
- 43846 describes the open Roux-en-Y approach. Choose 43644 when the documented operation is performed laparoscopically.
- 43775Sleeve gastrectomy
- 43775 is a laparoscopic sleeve procedure that removes part of the stomach; 43644 creates a pouch and connects it to the small intestine.
43644 billing questions
How does 43644 differ from 43645?
43644 describes a laparoscopic Roux-en-Y gastric bypass. 43645 is for a laparoscopic bypass that includes small-intestine reconstruction to limit absorption.
Can the pouch creation and intestinal connections be billed separately?
They are steps of the completed bypass reported under 43644, not separate reports of the same operation.
Does modifier 50 apply?
No. This is a single digestive-tract reconstruction, not surgery on paired anatomy.
What postoperative care is included?
The 90-day global period includes the day-before preoperative visit and 90 days of related postoperative care.
Can an assistant or co-surgeon be reported?
An assistant at surgery may be paid. Co-surgeons are paid only when supporting documentation is provided; 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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