$200.02–$253.35
31000 describes irrigation of the maxillary sinus. Choose 31090 for documented operative exploration, not lavage alone.
On this page
CMS RVU26D · Effective 2026-10-01
31090 Sinus exploration Medicare reimbursement rates in California
Reports operative exploration of paranasal sinus disease when the documented service is surgical exploration rather than irrigation or a more specifically defined sinus procedure. Compare 31090 office and facility rates across CMS payment localities in California.
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 31090 in California?
California has 29 payment localities in this comparison. Use the service location to choose the applicable amount. These are the supported base rates for the 29 payment areas shown below, using the same CMS release.
Office / nonfacility
No supported rate
Facility setting
$1050.00–$1289.53
29 of 29 localities have a supported rate.
Lowest: Chico
Highest: San Jose-Sunnyvale-Santa Clara (San Benito Cnty)
A spread of $239.53 per service.
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 31090 pays more and less in California
Otolaryngology surgery
About 31090: Surgical exploration of paranasal sinuses
Reports operative exploration of paranasal sinus disease when the documented service is surgical exploration rather than irrigation or a more specifically defined sinus procedure.
An otolaryngologist performs this operative service to explore sinus disease that requires surgical access, such as persistent or recurrent symptoms prompting assessment of the sinus cavity. The record should identify the clinical indication, sinus or sinuses explored, operative approach, findings, and work performed. This is distinct from flushing a sinus or simply examining the nasal passages with an endoscope.
Select the code when the documented operation matches sinus exploration and a more specific procedure code does not better describe the work. The CMS 90-day global period includes the day-before preoperative visit and 90 days of related postoperative care. When multiple procedures are performed in the same session, the highest-valued procedure is paid in full and the others at 50%. Bilateral reporting with modifier 50 is paid at 150%. Assistant-at-surgery payment is restricted; co-surgeons and team surgery are not permitted.
CMS billing rules for 31090
- Global period
- Major surgery with a 90-day global period: the day-before preoperative visit and 90 days of related postoperative care are included.
- Multiple procedures
- Standard multiple procedure reduction: the highest-valued procedure is paid in full and others at 50% when performed in the same session.
- Bilateral procedures
- Bilateral procedure with modifier 50 is paid at 150%.
- Assistant at surgery
- Statutory restriction: assistant at surgery is not paid.
- Co-surgeons
- Co-surgeons not permitted.
- Team surgery
- Team surgery not permitted.
Where the value comes from
- Work RVU10.89 · 36%
- Practice expense (office) RVU17.80 · 59%
- Malpractice RVU1.59 · 5%
63
Medicare services in 2024 · #5211 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.
31090 compared with similar codes
Office rates for California, from the same CMS release.
No office rate
31002 describes irrigation of the sphenoid sinus. It does not represent operative exploration.
$458.52–$578.41
31020 is directed to the maxillary sinus. Use it when the operative report supports that specific procedure rather than general sinus exploration.
No office rate
31050 is directed to the sphenoid sinus. The operative report should support the sinus-specific procedure to select it over 31090.
Compare 31090 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.
29 of 29 payment localities
| Payment locality | Office | Facility |
|---|---|---|
| Bakersfield | Office Unavailable | Facility $1054.60 |
| Chico | Office Unavailable | Facility $1050.00 |
| El Centro | Office Unavailable | Facility $1050.26 |
| Fresno | Office Unavailable | Facility $1050.00 |
| Hanford-Corcoran | Office Unavailable | Facility $1050.00 |
| Los Angeles-Long Beach-Anaheim (Los Angeles/Orange Cnty) | Office Unavailable | Facility $1117.25 |
| Madera | Office Unavailable | Facility $1050.00 |
| Merced | Office Unavailable | Facility $1050.00 |
| Modesto | Office Unavailable | Facility $1050.00 |
| Napa | Office Unavailable | Facility $1197.23 |
| Oxnard-Thousand Oaks-Ventura | Office Unavailable | Facility $1109.75 |
| Redding | Office Unavailable | Facility $1050.00 |
| Rest Of California | Office Unavailable | Facility $1050.00 |
| Riverside-San Bernardino-Ontario | Office Unavailable | Facility $1067.20 |
| Sacramento-Roseville-Folsom | Office Unavailable | Facility $1096.74 |
| Salinas | Office Unavailable | Facility $1092.54 |
| San Diego-Chula Vista-Carlsbad | Office Unavailable | Facility $1114.50 |
| San Francisco-Oakland-Berkeley (Marin Cnty) | Office Unavailable | Facility $1260.96 |
| San Francisco-Oakland-Berkeley (San Francisco/San Mateo/Alameda/Contra Costa Cnty) | Office Unavailable | Facility $1259.16 |
| San Jose-Sunnyvale-Santa Clara (San Benito Cnty) | Office Unavailable | Facility $1289.53 |
| San Jose-Sunnyvale-Santa Clara (Santa Clara Cnty) | Office Unavailable | Facility $1282.15 |
| San Luis Obispo-Paso Robles | Office Unavailable | Facility $1075.56 |
| Santa Cruz-Watsonville | Office Unavailable | Facility $1122.20 |
| Santa Maria-Santa Barbara | Office Unavailable | Facility $1095.61 |
| Santa Rosa-Petaluma | Office Unavailable | Facility $1133.20 |
| Stockton | Office Unavailable | Facility $1050.00 |
| Vallejo | Office Unavailable | Facility $1194.63 |
| Visalia | Office Unavailable | Facility $1050.00 |
| Yuba City | Office Unavailable | Facility $1050.00 |
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31090 billing questions
How is sinus exploration different from sinus irrigation?
Exploration describes an operative service to access and assess sinus disease. Codes 31000 and 31002 describe irrigation of the maxillary and sphenoid sinuses, respectively.
When should a sinus-specific procedure code be considered instead?
Use a more specific code when the operative report documents a procedure directed to a particular sinus, such as maxillary, sphenoid, or frontal sinus surgery.
What documentation supports reporting 31090?
Document the indication, sinus or sinuses explored, approach, operative findings, and work performed so the service can be distinguished from irrigation or a specifically coded operation.
How does the 90-day global period affect postoperative reporting?
The day-before preoperative visit and 90 days of related postoperative care are included in the global period.
Can modifier 50 be used for bilateral reporting?
CMS identifies this as a bilateral procedure; reporting with modifier 50 is paid at 150%.
Can an assistant or another surgeon be paid for this operation?
Assistant-at-surgery payment is subject to a statutory restriction. 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 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.
3,50731085,,Removal of frontal sinus,A,,15.25,15.89,NA,15.89,,2.21,33.35,33.35,0,090,0.10,0.76,0.14,2,1,2,1,0,9,,33.4009,09,0,99,0.00,0.00,0.00
3,50831086,,Removal of frontal sinus,A,,14.00,15.58,NA,15.58,,2.05,31.63,31.63,0,090,0.10,0.76,0.14,2,1,2,0,0,9,,33.4009,09,0,99,0.00,0.00,0.00
3,50931087,,Removal of frontal sinus,A,,14.21,13.68,NA,13.68,,2.07,29.96,29.96,0,090,0.10,0.76,0.14,2,1,2,1,0,9,,33.4009,09,0,99,0.00,0.00,0.00
3,51031090,,Exploration of sinuses,A,,10.89,17.80,NA,17.80,,1.59,30.28,30.28,0,090,0.10,0.76,0.14,2,1,1,0,0,9,,33.4009,09,0,99,0.00,0.00,0.00
3,5113110F,,Pres/absn hmrhg/lesion docd,I,,0.00,0.00,,0.00,,0.00,0.00,0.00,9,XXX,0.00,0.00,0.00,9,9,9,9,9,9,,33.4009,09,0,99,0.00,0.00,0.00
3,5123111F,,Ct/mri brain done w/in 24hrs,I,,0.00,0.00,,0.00,,0.00,0.00,0.00,9,XXX,0.00,0.00,0.00,9,9,9,9,9,9,,33.4009,09,0,99,0.00,0.00,0.00
3,5133112F,,Ct/mri brain done 24 hrs,I,,0.00,0.00,,0.00,,0.00,0.00,0.00,9,XXX,0.00,0.00,0.00,9,9,9,9,9,9,,33.4009,09,0,99,0.00,0.00,0.00