$2,733.87–$3,058.23
Code 31298 covers dilation of both frontal and sphenoid sinus ostia. Use 31297 when the reported dilation is confined to the sphenoid ostium.
On this page
CMS RVU26D · Effective 2026-10-01
31297 Sinus dilation Medicare reimbursement rates in Illinois
Endoscopic balloon dilation of the sphenoid sinus opening to improve drainage, reported when the surgeon treats the sphenoid ostium by dilation rather than sinusotomy. Compare 31297 office and facility rates across CMS payment localities in Illinois.
Amounts below use the non-QP conversion factor for participating physicians. These are base physician payments before claim-level adjustments, not patient costs or total hospital charges.
What does Medicare pay for 31297 in Illinois?
Illinois has 4 payment localities in this comparison. Use the service location to choose the applicable amount. These are the supported base rates for the 4 payment areas shown below, using the same CMS release.
Office / nonfacility
$1443.12–$1614.11
4 of 4 localities have a supported rate.
Facility setting
$127.56–$139.87
4 of 4 localities have a supported rate.
These are locality ranges, not averages or address-specific quotes. A facility-setting amount covers the physician service; it does not include a hospital’s separate bill. Choose a locality below to inspect its calculation, compare other payment areas, or price a percentage of Medicare.
Where 31297 pays more and less in Illinois
4 payment localities
$1443.12 to $1614.11
Nasal/sinus endoscopy
About 31297: Endoscopic sphenoid sinus dilation
Endoscopic balloon dilation of the sphenoid sinus opening to improve drainage, reported when the surgeon treats the sphenoid ostium by dilation rather than sinusotomy.
An otolaryngologist uses a nasal endoscope to reach and dilate the sphenoid sinus opening, commonly with a balloon catheter, to improve drainage through the natural ostium. The procedure may be performed in an office or operating room for a patient with sphenoid sinus disease or an obstructed sphenoid opening. Fluoroscopy, when used, is included in the service.
Report 31297 when the documented operative work is dilation of the sphenoid sinus ostium; distinguish it from a sphenoidotomy that opens the sinus by incision or removes tissue. The operative note should identify the treated sinus, side, endoscopic approach, and dilation performed. This is a 0-day global procedure, so same-day preoperative and postoperative care is included. Modifier 50 identifies bilateral treatment and CMS pays the bilateral procedure at 150%. When related endoscopies are performed together, endoscopy family pricing applies. An assistant is paid only when medical necessity is documented; co-surgeons and team surgery are not permitted.
CMS billing rules for 31297
- Global period
- Minor procedure with a 0-day global period: same-day preoperative and postoperative care is included.
- Multiple procedures
- Endoscopy family pricing applies when related endoscopies are performed together.
- Bilateral procedures
- Bilateral procedure with modifier 50 is paid at 150%.
- Assistant at surgery
- Assistant at surgery is paid only with documentation of medical necessity.
- Co-surgeons
- Co-surgeons not permitted.
- Team surgery
- Team surgery not permitted.
Where the value comes from
- Work RVU2.38 · 5%
- Practice expense (office) RVU44.10 · 94%
- Malpractice RVU0.36 · 1%
1.3K
Medicare services in 2024 · #2783 by national volume
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.
31297 compared with similar codes
Office rates for Illinois, from the same CMS release.
No office rate
Code 31287 is for endoscopic sphenoidotomy, while 31297 is for dilation of the sphenoid sinus opening.
No office rate
Code 31288 describes sphenoidotomy with tissue removal. Code 31297 describes sphenoid ostial dilation, not tissue removal.
Compare 31297 by payment locality
Find the payment area for your service address, then open its rate page for calculation inputs, release history and the percentage-of-Medicare tool. A city may cross payment-area boundaries; the ZIP lookup above helps resolve the location.
4 of 4 payment localities
Chicago →
Office / nonfacility
$1587.99
Facility
$139.87
East St. Louis →
Office / nonfacility
$1458.85
Facility
$133.21
Rest Of Illinois →
Office / nonfacility
$1443.12
Facility
$127.56
Suburban Chicago →
Office / nonfacility
$1614.11
Facility
$134.29
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31297 billing questions
How does 31297 differ from sphenoidotomy code 31287?
Use 31297 for dilation of the sphenoid sinus opening. Code 31287 describes endoscopic sphenoidotomy rather than ostial dilation.
Does 31297 include fluoroscopy?
Yes. Fluoroscopy, when performed as part of the sphenoid ostial dilation, is included in this service.
When is modifier 50 appropriate?
Use modifier 50 when the surgeon dilates both sphenoid sinus ostia. CMS pays the bilateral procedure at 150%.
What happens when another related sinus endoscopy is performed in the same session?
CMS endoscopy family pricing applies when related endoscopies are performed together. The operative documentation should support each distinct sinus procedure reported.
Can an assistant surgeon be reported?
Assistant-at-surgery payment is available only when the documentation establishes medical necessity. Co-surgeons and team surgery are not permitted for this code.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense, and malpractice RVUs, adjusted by each locality’s geographic indices and the applicable conversion factor. Unavailable or separately priced services are labeled rather than assigned a made-up amount.
Source: RVU26D. Effective 2026-10-01 through the day before 2027-01-01.
3,54931294,,Nsl/sins ndsc surg on dcmprn,A,,19.80,8.80,NA,8.80,,2.90,31.50,31.50,0,010,0.10,0.80,0.10,3,1,0,0,0,9,31231,33.4009,09,0,99,0.00,0.00,0.00
3,55031295,,Nsl/sins ndsc surg max sins,A,,2.63,44.21,,1.02,,0.39,47.23,4.04,0,000,0.00,0.00,0.00,3,1,2,0,0,9,31231,33.4009,09,0,99,0.00,0.00,0.00
3,55131296,,Nsl/sins ndsc surg frnt sins,A,,3.02,44.55,,1.11,,0.43,48.00,4.56,0,000,0.00,0.00,0.00,3,1,2,0,0,9,31231,33.4009,09,0,99,0.00,0.00,0.00
3,55231297,,Nsl/sins ndsc surg sphn sins,A,,2.38,44.10,,0.96,,0.36,46.84,3.70,0,000,0.00,0.00,0.00,3,1,0,0,0,9,31231,33.4009,09,0,99,0.00,0.00,0.00
3,55331298,,Nsl/sins ndsc surg frnt&sphn,A,,4.39,83.78,,1.45,,0.62,88.79,6.46,0,000,0.00,0.00,0.00,3,1,0,0,0,9,31231,33.4009,09,0,99,0.00,0.00,0.00
3,55431299,,Unlisted px accessory sinus,C,,0.00,0.00,,0.00,,0.00,0.00,0.00,0,YYY,0.00,0.00,0.00,2,0,0,1,1,9,,33.4009,09,0,99,0.00,0.00,0.00
3,55531300,,Removal of larynx lesion,A,,15.51,15.81,NA,15.81,,2.26,33.58,33.58,0,090,0.10,0.76,0.14,2,0,2,1,0,9,,33.4009,09,0,99,0.00,0.00,0.00