Billing code 31298: Sinus dilationMedicare rate & RVUs

Endoscopic dilation of frontal and sphenoid sinus openings is reported when both drainage pathways are treated during the same operative session.

CMS RVU26DEffective Oct 1, 2026109 payment localities9.3K Medicare services in 2024

Medicare pays $2,965.67 for 31298 nationally in the office and $215.77 in a hospital or facility. Local office rates run $2,561.06–$4,209.05.

Medicare rate · 31298

Sinus dilation

Work RVUs
4.39
Total RVUs
88.79
Global days
000

National rate · 2026

$2,965.67

Office setting, before claim adjustments.

See every locality for 31298 →Billed by an NP, PA or therapist? →

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 10 sections
  1. Medicare rate
  2. What 31298 covers
  3. By payment locality
  4. Rate map
  5. How it’s calculated
  6. Payment rules
  7. Similar codes
  8. Related codes
  9. Billing questions
  10. Sources

What 31298 covers

An otolaryngologist uses a nasal endoscope to access and enlarge the frontal and sphenoid sinus openings, commonly with a balloon catheter passed through the nasal cavity. The procedure may be performed for obstructed sinus drainage, including in patients with chronic rhinosinusitis, when the operative plan is dilation at both sites. It is typically performed in an operating or procedural setting; the record should identify each sinus treated and the dilation performed.

Report 31298 when both frontal and sphenoid openings are dilated during the operative session; single-sinus dilation codes distinguish treatment of only one site. Document the treated anatomy, laterality, and technique. CMS assigns a 0-day global period, so same-day preoperative and postoperative care is included. Related endoscopies performed together are subject to endoscopy-family pricing. For bilateral work, modifier 50 is paid at 150%. Assistant-at-surgery payment requires documented medical necessity; 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 31298 pays more and less

The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.

109 payment localities

$2561.06 to $4209.05

$2561.06$3385.06$4209.05
One dot per payment locality, office / nonfacility. Hover a dot to see the locality; select it to open that rate.

109 of 109 payment localities

31298 office and facility rates by payment locality
Payment localityOfficeFacility
Alabama$2,606.89$200.73
Alaska*$3,211.57$282.93
Arizona$2,875.94$211.29
Arkansas$2,561.06$198.90
Atlanta$3,015.04$221.15
Austin$3,125.90$216.51
Bakersfield$3,228.99$215.11
Baltimore/Surr. Cntys$3,177.20$226.56
Beaumont$2,712.35$209.94
Brazoria$2,937.10$211.95

31298 rates by state

Office rate range in each state. Select a state to see its payment localities.

Explore a state

Local rates. Clear comparisons.

Hover or focus a tile to see its rate range. Select it to open the state’s fee schedule.

$2,561.06

$3,718.12

Color shows the midpoint of each state’s locality range.

View every state and territory as a table
31298 office rate range by state
State / territoryOffice rate rangeLocalities
AK$3,211.571
AL$2,606.891
AR$2,561.061
AZ$2,875.941
CA$3,227.19–$4,209.0529
CO$3,141.981
CT$3,188.421
DC$3,474.031
DE$2,930.731
FL$2,852.96–$3,112.063
GA$2,667.42–$3,015.042
GU$3,340.321
HI$3,340.321
IA$2,715.321
ID$2,730.891
IL$2,733.87–$3,058.234
IN$2,750.741
KS$2,686.761
KY$2,653.291
LA$2,642.99–$2,803.382
MA$3,112.12–$3,512.282
MD$2,999.01–$3,474.033
ME$2,733.97–$2,932.842
MI$2,724.88–$2,881.932
MN$3,032.241
MO$2,578.96–$2,831.393
MS$2,571.291
MT$2,965.621
NC$2,770.701
ND$2,953.371
NE$2,737.311
NH$3,077.811
NJ$3,230.99–$3,424.042
NM$2,737.571
NV$2,965.011
NY$2,819.60–$3,521.685
OH$2,722.381
OK$2,661.631
OR$2,948.32–$3,273.322
PA$2,735.06–$3,087.032
PR$2,996.141
RI$3,058.561
SC$2,749.891
SD$2,951.921
TN$2,701.431
TX$2,712.35–$3,125.908
UT$2,795.651
VA$2,912.01–$3,474.032
VI$2,996.141
VT$2,927.451
WA$3,110.93–$3,604.432
WI$2,833.811
WV$2,608.011
WY$2,960.281

How the 31298 rate is calculated

Each of 31298’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 · 31298

RVUs × geographic indexes × conversion factor

Work4.39

4.39 RVUs× 1.000 GPCI

Practice expense83.78

83.78 RVUs× 1.000 GPCI

Malpractice0.62

0.62 RVUs× 1.000 GPCI

Adjusted RVUs

88.7900

Conversion factor

$33.4009

Medicare rate

$2,965.67

Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.

Payment rules and modifiers for 31298

The CMS indicators that decide how 31298 is paid alongside other services.

CMS payment indicators · 31298

Sinus dilation

RuleCMS valueWhat it means
Global period000Same-day global: pre- and post-op care on the day of the procedure is included.
Multiple procedures3Endoscopy family rules apply.
Bilateral (modifier 50)1Bilateral with modifier 50 pays 150% of the fee schedule amount.
Assistant at surgery (80/81/82/AS)0Not paid without supporting documentation.
Co-surgeons (62)0Not permitted.
Team surgery (66)0Not permitted.
Professional/technical0Physician service: no professional/technical split.

What modifiers do to the payment

Modifier 50 · payment effect

With and without the modifier

31298 without 50 · national office

$2,965.67

Sinus dilation

31298-50 · Bilateral: 150%

$4,448.51

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).

When to use modifier 50

31298 compared with similar codes

Compare codes · National

5 codes, side by side

  • 31298

    Sinus dilation4.39 wRVU

    $2,965.67

  • 31296

    Sinus dilation3.02 wRVU

    $1,603.24−$1,362.43

  • 31297

    Sinus dilation2.38 wRVU

    $1,564.50−$1,401.17

  • 31276

    Frontal sinus endoscopy6.58 wRVU

    Not priced

  • 31287

    Sphenoidotomy3.41 wRVU

    Not priced

How to choose

31296Sinus dilation
31296 describes dilation of the frontal sinus opening alone. Choose 31298 when the sphenoid opening is also dilated in the session.
31297Sinus dilation
31297 describes dilation of the sphenoid sinus opening alone. Choose 31298 when the frontal opening is also dilated in the session.
31276Frontal sinus endoscopy
31276 is frontal sinus endoscopic surgery involving tissue removal; 31298 describes dilation of the frontal and sphenoid openings.
31287Sphenoidotomy
31287 is endoscopic sphenoid sinus surgery without tissue removal, not dilation of both the sphenoid and frontal openings.

31298 billing questions

When should I choose 31298 over 31296 or 31297?

Use 31298 when the frontal and sphenoid sinus openings are both dilated. Codes 31296 and 31297 describe dilation at the frontal and sphenoid sites, respectively, when only one of those sites is treated.

Does 31298 include maxillary sinus dilation?

No. This code identifies dilation of the frontal and sphenoid openings. The maxillary sinus dilation code is 31295.

How should I report bilateral dilation?

CMS identifies this as a bilateral procedure; modifier 50 is paid at 150%. The operative documentation should support treatment on both sides.

How does payment work when related endoscopies are performed together?

CMS applies endoscopy-family pricing when related endoscopies are performed together. The same-day preoperative and postoperative care is included in the 0-day global period.

What documentation supports reporting 31298?

Document endoscopic dilation of both the frontal and sphenoid sinus openings, along with the treated side or sides and the technique performed. Assistant-at-surgery payment requires documentation of medical necessity.

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
RVUs for 31298PPRRVU2026_Oct_nonQPP.csv, line 3,553 (RVU26D)

Open CMS sourceHow we calculate rates

Did this answer your question about what 31298 pays?

Tell us what you were actually trying to work out. We’ll answer you directly, or build the page that does.

Fee sheets

Put 31298 and the rest of your codes on one sheet

Build a fee sheet from your own code list at your locality, put your payer contracts beside Medicare, and see what changed each quarter.

Build my fee sheetOr price your code list free →