$46.25–$49.15
94727 uses gas dilution or washout to measure lung volumes; 94729 measures gas transfer into blood with carbon monoxide. Both may be reported when each service is performed.
On this page
CMS RVU26D · Effective 2026-10-01
94729 Diffusing capacity (DLCO) Medicare reimbursement rates in Maine
Add-on code for measuring the lungs’ carbon monoxide diffusing capacity, reported with an eligible primary pulmonary function test during the same session. Compare 94729 office and facility rates across CMS payment localities in Maine.
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 94729 in Maine?
Maine has 2 payment localities in this comparison. Use the service location to choose the applicable amount. These are the supported base rates for the 2 payment areas shown below, using the same CMS release.
Office / nonfacility
$58.69–$62.71
2 of 2 localities have a supported rate.
Facility setting
No supported rate
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.
Pulmonary function testing
About 94729: Carbon monoxide diffusing capacity test add-on
Add-on code for measuring the lungs’ carbon monoxide diffusing capacity, reported with an eligible primary pulmonary function test during the same session.
Diffusing capacity testing evaluates gas transfer from the alveoli into pulmonary capillary blood. In the common single-breath method, the patient inhales a small amount of carbon monoxide with a tracer gas, holds the breath briefly, then exhales into an analyzer. Pulmonologists order it to assess interstitial lung disease, emphysema, pulmonary hypertension, amiodarone toxicity, or fitness for lung resection. Respiratory therapists and PFT technologists perform it in pulmonary offices or hospital labs; a physician interprets the result, sometimes adjusted for hemoglobin.
Report 94729 once per testing session with an eligible primary PFT code, such as spirometry (94010 or 94060), lung volumes (94726 or 94727), oscillometry (94728), bronchospasm provocation (94070), or flow-volume testing (94375). Repeat maneuvers for test quality remain within that unit. Document the measured capacity, test quality, any hemoglobin adjustment, and an interpretation when billing the professional service. CMS pays this add-on within the primary procedure’s global period. Modifier 26 identifies the professional interpretation; modifier TC identifies equipment and staff work. Bill without a component modifier when the same entity provides both components.
CMS billing rules for 94729
- Global period
- Add-on code: billed only together with a primary procedure and paid within that procedure's global period.
- Professional and technical components
- Diagnostic test with a professional component (modifier 26, interpretation) and a technical component (modifier TC, equipment and staff); billing without a modifier is the global service.
Where the value comes from
- Work RVU0.19 · 10%
- Practice expense (office) RVU1.69 · 89%
- Malpractice RVU0.02 · 1%
976.1K
Medicare services in 2024 · #147 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.
94729 compared with similar codes
Office rates for Maine, from the same CMS release.
$59.06–$62.94
94726 measures lung volumes in a body box and may include airway resistance. 94729 measures diffusing capacity and is reported alongside an eligible primary test, not as a substitute.
$27.60–$29.27
94010 measures airflow and vital capacity by spirometry and can serve as a primary code; 94729 adds a gas-transfer measurement and requires an eligible primary test.
94760
No office rateN-invas ear/pls oximetry 1
94760 captures a single pulse oximetry determination of oxygen saturation, not the alveolar-capillary gas-transfer measurement obtained with DLCO testing.
Compare 94729 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.
2 of 2 payment localities
Rest Of Maine →
Office / nonfacility
$58.69
Facility
Unavailable
Southern Maine →
Office / nonfacility
$62.71
Facility
Unavailable
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94729 billing questions
Can 94729 be billed when DLCO is the only test performed?
No. It is an add-on and must be reported with an eligible primary pulmonary function code, such as 94010, 94060, 94726, 94727, 94728, 94070, or 94375.
How many units of 94729 are reported per session?
Report one unit per testing session. Multiple DLCO maneuvers performed to obtain reproducible results are part of that service.
Which modifier does the pulmonologist use when reading DLCO in a hospital PFT lab?
Report 94729 with modifier 26 for the physician’s interpretation. The hospital reports the technical portion with modifier TC.
Is a hemoglobin correction billed separately?
The calculation adjustment for hemoglobin is part of interpreting DLCO. A separately performed hemoglobin laboratory test is a distinct service when supported and reportable.
Can 94729 be reported with both 94726 and 94727?
94729 may accompany either lung-volume method. Do not report both lung-volume codes for the same set of measurements; select the method performed.
What documentation supports 94729?
The PFT report should show measured DLCO, predicted and percent-predicted results, test quality or reproducibility, and any hemoglobin adjustment. A professional or global claim also requires the physician’s interpretation.
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.
12,43694728,,Airwy resist by oscillometry,A,,0.25,1.17,,1.17,NA,0.02,1.44,1.44,1,XXX,0.00,0.00,0.00,0,0,0,0,0,9,,33.4009,09,0,99,0.00,0.00,0.00
12,43794728,26,Airwy resist by oscillometry,A,,0.25,0.11,,0.11,,0.01,0.37,0.37,1,XXX,0.00,0.00,0.00,0,0,0,0,0,9,,33.4009,09,0,99,0.00,0.00,0.00
12,43894728,TC,Airwy resist by oscillometry,A,,0.00,1.06,,1.06,NA,0.01,1.07,1.07,1,XXX,0.00,0.00,0.00,0,0,0,0,0,9,,33.4009,01,0,99,0.00,0.00,0.00
12,43994729,,Diffusing capacity,A,,0.19,1.69,,1.69,NA,0.02,1.90,1.90,1,ZZZ,0.00,0.00,0.00,0,0,0,0,0,9,,33.4009,09,0,99,0.00,0.00,0.00
12,44094729,26,Diffusing capacity,A,,0.19,0.08,,0.08,,0.01,0.28,0.28,1,ZZZ,0.00,0.00,0.00,0,0,0,0,0,9,,33.4009,09,0,99,0.00,0.00,0.00
12,44194729,TC,Diffusing capacity,A,,0.00,1.61,,1.61,NA,0.01,1.62,1.62,1,ZZZ,0.00,0.00,0.00,0,0,0,0,0,9,,33.4009,01,0,99,0.00,0.00,0.00
12,44294760,,N-invas ear/pls oximetry 1,T,,0.00,0.11,,0.11,NA,0.01,0.12,0.12,3,XXX,0.00,0.00,0.00,0,0,0,0,0,9,,33.4009,01,0,99,0.00,0.00,0.00