CPT code 94640: Inhalation treatment2026 Medicare rate & RVUs in Illinois
Reports an inhalation treatment delivered for acute airway obstruction or diagnostic sputum induction, such as nebulized medication for an acute episode.
Medicare pays $8.15–$9.17 for 94640 in the office in Illinois, from Rest Of Illinois to Suburban Chicago. 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 94640 covers
This service covers an intermittent inhalation treatment delivered through a nebulizer, aerosol generator, metered-dose inhaler, or similar device to relieve acute airway obstruction or induce sputum for diagnostic testing. A common situation is nebulized bronchodilator treatment for a patient with acute wheezing or an asthma or COPD exacerbation. Physicians, nurses, and respiratory therapists may be involved in delivering the treatment in an office, clinic, or hospital setting.
Report one unit for an episode of care, even when the patient receives multiple inhalation treatments during that episode. For separate episodes on the same date, follow CPT reporting guidance for distinct episodes. Document the clinical reason, device or method, treatment provided, and the patient’s response. When billed as an incident-to service, CMS requires performance under physician supervision.
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 94640 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.
4 payment localities
$8.15 to $9.17
| Payment locality | Office | Facility |
|---|---|---|
| Chicago | $9.16 | Unavailable |
| East St. Louis | $8.35 | Unavailable |
| Rest Of Illinois | $8.15 | Unavailable |
| Suburban Chicago | $9.17 | Unavailable |
How the 94640 rate is calculated
Each of 94640’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 · 94640
RVUs × geographic indexes × conversion factor
Work0.00
0.00 RVUs× 1.000 GPCI
Practice expense0.25
0.25 RVUs× 1.000 GPCI
Malpractice0.01
0.01 RVUs× 1.000 GPCI
Adjusted RVUs
0.2600
Conversion factor
$33.4009
Medicare rate
$8.68
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for 94640
The CMS indicators that decide how 94640 is paid alongside other services.
CMS payment indicators · 94640
Inhalation treatment
| Rule | CMS value | What it means |
|---|---|---|
| Global period | XXX | The global surgery concept doesn’t apply. |
| Multiple procedures | 0 | No multiple-procedure reduction. |
| 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) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 5 | Incident-to service. |
94640 compared with similar codes
Compare codes · National
4 codes, side by side
How to choose
- 94642Aerosol inhalation treatment
- 94640 covers intermittent treatment for acute airway obstruction or diagnostic sputum induction. 94642 is a separate aerosol-treatment code associated with a specified drug.
- 94644Continuous inhalation
- Choose 94640 for intermittent inhalation treatment; 94644 describes continuous treatment and covers its first hour.
- 94664Inhaler training
- 94640 is treatment delivery. 94664 is demonstration or evaluation of the patient’s use of an inhalation device, not medication treatment.
94640 billing questions
Is 94640 reported for every nebulizer treatment?
No. Report one unit for the episode of care, regardless of the number of inhalation treatments provided during that episode. Distinct episodes on the same date are subject to CPT reporting guidance.
When is 94640 preferable to continuous inhalation treatment?
Use 94640 for an intermittent treatment for acute airway obstruction or diagnostic sputum induction. Code 94644 describes continuous inhalation treatment, with 94645 for each additional hour.
Can a nurse or respiratory therapist provide the service?
They may be involved in delivering it. When the service is billed as incident-to, it must be performed under physician supervision.
What documentation supports 94640?
Document the acute obstruction or diagnostic sputum-induction purpose, the treatment and delivery method, and the patient’s response. The record should support the reported episode of care.
Is inhaler instruction part of 94640?
No. 94640 represents treatment delivery, while 94664 is for demonstrating or evaluating the patient’s use of an inhalation device. Report the latter only when that distinct teaching or evaluation service is performed and supported.
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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