Billing code 31231: Nasal endoscopyMedicare rate & RVUs in Oregon
Report diagnostic nasal endoscopy for endoscopic inspection of the nasal passages, meatuses, and sphenoethmoid recess without sinus entry or surgical treatment.
Medicare pays $191.19–$209.50 for 31231 in the office in Oregon, from Rest Of Oregon to Portland. Which amount applies depends on the service address.
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 31231 covers
An otolaryngologist, and sometimes an allergist or advanced practice provider, uses a rigid or flexible scope to inspect the nasal cavity in an office or outpatient facility. Topical decongestant or anesthetic may be used. The examination can show the septum, turbinates, middle meatus, sphenoethmoid recess, and nasopharynx when visualized. Common indications include chronic rhinosinusitis, nasal obstruction, recurrent epistaxis, suspected polyps or masses, and surveillance after sinus surgery when no debridement is performed.
Report one unit whether one or both sides are examined; the code is already priced as bilateral, so modifier 50 adds no payment. Document the indication, sides examined, structures viewed, and findings. Its 0-day global period includes same-day pre- and post-procedure care. A separately identifiable E/M service beyond that care may be reported with modifier 25 on the E/M code. For multiple procedures in the same session, the highest-valued is paid in full and other procedures subject to the standard reduction are paid at 50%. Medicare does not pay an assistant at surgery or permit co-surgeons or team surgery for this code.
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 31231 pays more and less in Oregon
| Payment locality | Office | Facility |
|---|---|---|
| Portland | $209.50 | $55.50 |
| Rest Of Oregon | $191.19 | $53.14 |
How the 31231 rate is calculated
Each of 31231’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 · 31231
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 1.07Practice expense 4.56Malpractice 0.16
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 31231
The CMS indicators that decide how 31231 is paid alongside other services.
CMS payment indicators · 31231
Nasal endoscopy
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 000 | Same-day global: pre- and post-op care on the day of the procedure is included. |
| Multiple procedures | 2 | Standard reduction: highest-valued procedure at 100%, others at 50%. |
| Bilateral (modifier 50) | 2 | Already bilateral by definition: paid once at 100%. |
| 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. |
What modifiers do to the payment
Modifier 51 · payment effect
With and without the modifier
31231 without 51 · national office
$193.39
Nasal endoscopy
31231-51 · Second procedure: 50%
$96.70
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%).
31231 compared with similar codes
Compare codes
31231 vs 31233 vs 31237 vs 92511 vs 31575: national Medicare rates
Swap in your local Medicare rate.
How to choose
- 31233Sinus endoscopy
- 31231 inspects the nasal cavity and sinus openings without entering a sinus. 31233 includes direct examination inside the maxillary sinus.
- 31237Nasal endoscopy
- Use 31237 when the nasal or sinus endoscopy includes biopsy, polyp removal, or debridement. Do not separately report 31231 for diagnostic inspection of the same site during that surgical endoscopy.
- 92511Nasopharyngoscopy
- 92511 focuses on the nasopharynx. 31231 evaluates nasal cavity structures such as the meatuses, turbinates, and sphenoethmoid recess, even if the nasopharynx is also visualized.
- 31575Laryngoscopy
- 31575 examines the larynx with a flexible scope. Passing that scope through the nose does not alone support 31231; a separate medically necessary nasal cavity examination must be documented.
31231 billing questions
Should modifier 50 or RT/LT be added when both sides of the nose are scoped?
No. Report one unit for a bilateral examination without modifier 50 or RT/LT; the code is already priced as bilateral.
Can this code be billed with a surgical sinus endoscopy on the same side?
Do not separately report the diagnostic inspection of the same site during a surgical nasal or sinus endoscopy. Report the applicable surgical code when biopsy, polyp removal, or ethmoidectomy is performed.
When should 31233 or 31235 be reported instead?
Use 31233 for diagnostic maxillary sinusoscopy and 31235 for diagnostic sphenoid sinusoscopy. Inspection of the nasal cavity and sinus openings without entering either sinus remains 31231.
Can an office visit be billed on the same day as the endoscopy?
Yes, if the E/M service is significant and separately identifiable from the routine assessment and same-day care included with the endoscopy. Append modifier 25 to the E/M code.
Does passing a flexible laryngoscope through the nose support a separate nasal endoscopy?
No. Transnasal passage to examine the larynx does not by itself establish a separate diagnostic nasal examination. Report 31231 only when a medically necessary nasal cavity examination is separately performed and documented.
What documentation supports the procedure?
Record the indication, sides examined, structures viewed, and endoscopic findings. Document the scope type and any anesthetic or decongestant used; a note stating only “nasal exam” does not establish the endoscopic examination.
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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