CPT code 42999: Unlisted throat procedure, pharynx, adenoids, or tonsils2026 Medicare rate & RVUs in Illinois
An unlisted surgical code for procedures involving the pharynx, adenoids, or tonsils when no specific CPT code describes the work performed.
CMS doesn’t publish an office rate for 42999 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.
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On this page 9 sections
What 42999 covers
CPT 42999 is used for an operation involving the pharynx, adenoids, or tonsils when no more specific CPT code describes the service. Otolaryngologists and head-and-neck surgeons may report it for uncommon operative work in these areas. It is not the selection for a routine, specifically described tonsillectomy, adenoidectomy, or combined procedure when a listed code fits. The claim should identify the procedure performed and include an operative report explaining the work and why a listed code does not describe it.
Medicare assigns this code physician fee schedule status C, or carrier priced: there is no national payment amount, and the Medicare Administrative Contractor sets payment for each claim. The contractor also sets the global period. When multiple procedures are performed in the same session, the highest-valued procedure is paid in full and other procedures are reduced to 50%.
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 42999 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, IL | Unavailable | Unavailable |
| East St. Louis, IL | Unavailable | Unavailable |
| Rest of Illinois | Unavailable | Unavailable |
| Suburban Chicago, IL | Unavailable | Unavailable |
How the 42999 rate is calculated
Each of 42999’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 · 42999
RVUs × geographic indexes × conversion factor
Work0.00
0.00 RVUs× 1.000 GPCI
Practice expense0.00
0.00 RVUs× 1.000 GPCI
Malpractice0.00
0.00 RVUs× 1.000 GPCI
Adjusted RVUs
0.0000
Conversion factor
$33.4009
Medicare rate
$0.00
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for 42999
The CMS indicators that decide how 42999 is paid alongside other services.
CMS payment indicators · 42999
Unlisted throat procedure, pharynx, adenoids, or tonsils
| Rule | CMS value | What it means |
|---|---|---|
| Global period | YYY | The Medicare contractor sets the global period. |
| Multiple procedures | 2 | Standard reduction: highest-valued procedure at 100%, others at 50%. |
| Bilateral (modifier 50) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 0 | Not paid without supporting documentation. |
| Co-surgeons (62) | 1 | Permitted with supporting documentation. |
| Team surgery (66) | 1 | Permitted with supporting documentation. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
What modifiers do to the payment
Modifier 51 · payment effect
With and without the modifier
42999 without 51 · national facility
$0.00
Unlisted throat procedure, pharynx, adenoids, or tonsils
42999-51 · Second procedure: 50%
$0.00
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%).
42999 compared with similar codes
Compare codes · National
5 codes, side by side
How to choose
- 42820Tonsil and adenoid removalPatient younger than 12
- 42820 describes a listed combined tonsil and adenoid removal for a patient younger than 12. Use 42999 only when the actual operation lacks a specific listed code.
- 42821Tonsil and adenoid removalAge 12 or older
- 42821 describes a listed combined tonsil and adenoid removal for a patient age 12 or older. It is more specific than 42999 when that operation was performed.
- 42900Pharyngeal repairWound closure
- 42900 is for a defined repair of a throat wound. 42999 is for a different pharyngeal, adenoid, or tonsillar procedure without a specific code.
- 42950PharyngoplastyReconstruction of the pharynx
- 42950 describes a listed throat reconstruction. Choose 42999 only when the procedure performed is not represented by that or another specific code.
42999 billing questions
When should I report 42999 instead of a tonsil or adenoid code?
Use 42999 only when the operation on the pharynx, adenoids, or tonsils is not described by a more specific CPT code. Use the listed code when it accurately describes the procedure performed.
What documentation should accompany a 42999 claim?
Include an operative report describing the procedure, the anatomy treated, and the work performed. Explain why a listed CPT code does not adequately describe it.
How does Medicare determine payment for 42999?
Status C means the Medicare Administrative Contractor sets payment for each claim; CMS publishes no national payment amount for this code.
Who sets the global period for 42999?
The Medicare contractor sets the global period for this unlisted procedure.
How is 42999 treated with other procedures in the same session?
The highest-valued procedure is paid in full, and other procedures are reduced to 50%.
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
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