Billing code 31051: Sphenoid surgeryMedicare rate & RVUs in Illinois
Reports surgery opening a sphenoid sinus and removing tissue, such as diseased mucosa or a lesion, when documented in the operative report.
CMS doesn’t publish an office rate for 31051 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 31051 covers
This service involves surgically opening the sphenoid sinus and removing tissue from within it. Otolaryngologists commonly perform it in an operating room for sphenoid disease requiring more than irrigation or an opening alone. The operative report should identify the sphenoid sinus treated and describe both the surgical opening and the tissue removed.
Report this code when tissue removal accompanies the sphenoid sinus surgery; an opening without tissue removal is represented by a different code. CMS assigns a 90-day global period, including the day-before preoperative visit and 90 days of related postoperative care. For multiple procedures in one session, the highest-valued procedure is paid in full and other procedures are subject to the standard 50% reduction. Bilateral reporting with modifier 50 is paid at 150%. Medicare does not pay an assistant at surgery for this service; co-surgeons and team surgery are 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 31051 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 | $684.18 |
| East St. Louis | Unavailable | $641.72 |
| Rest Of Illinois | Unavailable | $623.36 |
| Suburban Chicago | Unavailable | $673.84 |
How the 31051 rate is calculated
Each of 31051’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 · 31051
RVUs × geographic indexes × conversion factor
Work7.07
7.07 RVUs× 1.000 GPCI
Practice expense10.90
10.90 RVUs× 1.000 GPCI
Malpractice1.05
1.05 RVUs× 1.000 GPCI
Adjusted RVUs
19.0200
Conversion factor
$33.4009
Medicare rate
$635.29
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for 31051
31051 has a 90-day global period: related visits in that window are included in the surgery payment.
CMS payment indicators · 31051
Sphenoid surgery
| 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) | 1 | Not paid (statutory restriction). |
| Co-surgeons (62) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
| Split (54/55/56) | 0.10/0.76/0.14 | Share of the payment for pre-op, the procedure itself, and post-op care. |
Global surgery period · 31051
Sphenoid surgery
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
31051 without 50 · national facility
$635.29
Sphenoid surgery
31051-50 · Bilateral: 150%
$952.94
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).
31051 compared with similar codes
Compare codes · National
4 codes, side by side
How to choose
- 31050Sphenoid sinus surgery
- Choose 31051 when tissue is removed from the sphenoid sinus; 31050 represents sphenoid surgery without tissue removal.
- 31287Sphenoidotomy
- 31287 describes endoscopic sphenoid surgery without tissue removal. This code includes tissue removal and does not specify an endoscopic approach.
- 31288Sphenoid surgery
- 31288 describes endoscopic sphenoid surgery with tissue removal. Use the code that fits the documented approach and service.
31051 billing questions
How does this differ from 31050?
Use 31051 when tissue is removed from the sphenoid sinus during surgery. Code 31050 represents sphenoid sinus surgery without that tissue removal.
How does this differ from 31288?
Code 31288 describes endoscopic sphenoid sinus surgery with tissue removal. Choose the code that matches the documented surgical approach and service.
What should the operative report document?
Document the sphenoid sinus treated, the surgical opening, and the tissue removed. The record should make clear that tissue removal was part of the procedure.
How is bilateral surgery reported?
For bilateral surgery, report modifier 50; CMS pays this code at 150% when billed bilaterally.
Are assistant or co-surgeon services payable?
Medicare does not pay an assistant at surgery for this code. Co-surgeons and team surgery are 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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