CPT code 94729: Diffusing capacity (DLCO), add-on to pulmonary function testing2026 Medicare rate & RVUs in Iowa

In Iowa, Medicare pays $58.26 for 94729 in the office.

Check a contract rate as a % of Medicare · 94729 nationwide

Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.

What 94729 covers

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.

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.

How Iowa compares for 94729

Across 109 of 109 payment localities, the office rate for 94729 runs from $55.18 in Arkansas to $88.80 in San Benito County, CA. Iowa pays $58.26. The RVUs are the same everywhere; the geographic indexes change the dollars.

Every other payment area

94729 rates by state

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

See 94729 in every payment locality

How the 94729 rate is calculated

Each of 94729’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.

Payment rules and modifiers for 94729

The CMS indicators that decide how 94729 is paid alongside other services.

What modifiers do to the payment

When to use modifier 26

Codes related to 94729

Related codes aren’t interchangeable: bill the code that matches the service performed.

How 94729 has changed in Iowa

Price 94729 for an earlier date of service

Where the Iowa rate applies

Iowa is a Medicare payment area, not a city. Our Census mapping connects it to 1026 cities and communities in Iowa. Some span more than one payment area; confirm with the service ZIP.

• Ackley
• Ackworth
• Adair
• Adel
• Afton
• Agency
• Ainsworth
• Akron

Browse all communities in Iowa

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

Open CMS sourceHow we calculate rates