A4604 HCPCS code: Tubing with integrated heating element for use with positive airway pressure device
A4604 is the HCPCS Level II code for tubing with integrated heating element for use with positive airway pressure device. The 2026 Medicare DMEPOS fee schedule pays $49.31 to $76.79 (NU, new equipment, purchased) depending on the state. Its Medicare coverage code is C (Carrier judgment): Coverage is decided by the Medicare contractor (MAC) case by case. The NCCI unit limit is 1 per day on DME suppliers. Medicare volume rose 25% from 2022 to 2024 (2,440,401 to 3,056,009 services). In 2024, 4,336 suppliers billed Medicare for A4604 (purchases), serving 1,314,262 beneficiaries; California, Florida, Texas accounted for 21% of services. Its average fee ranks 11 of 13 A46 codes billed NU (family range $2.30–$66.87); rural fees run 33% higher.
Code details
| Field | Value |
|---|---|
| Section | A codes — Transportation, medical/surgical supplies and miscellaneous |
| Coverage code | C — Carrier judgment |
| Pricing indicator | 32 — DMEPOS: inexpensive or routinely purchased item |
| BETOS category | D1E — Other durable medical equipment |
| Added | 2006-01-01 |
| Last action effective | 2006-01-01 |
2026 Medicare DMEPOS fee schedule for A4604
| Modifier | Meaning | Lowest state fee | Highest state fee | Ceiling | Floor |
|---|---|---|---|---|---|
| NU | new equipment, purchased | $49.31 | $76.79 | — | — |
| State | Modifier | Fee | Rural fee |
|---|---|---|---|
| AK | NU | $68.58 | — |
| AL | NU | $49.36 | $68.75 |
| AR | NU | $49.36 | $68.75 |
| AZ | NU | $49.52 | $68.75 |
| CA | NU | $50.66 | $68.75 |
| CO | NU | $50.59 | $68.75 |
| CT | NU | $52.55 | $68.75 |
| DC | NU | $49.98 | $68.75 |
| DE | NU | $49.98 | $68.75 |
| FL | NU | $49.36 | $68.75 |
| GA | NU | $49.36 | $68.75 |
| HI | NU | $68.58 | — |
| IA | NU | $49.31 | $68.75 |
| ID | NU | $50.59 | $68.75 |
| IL | NU | $49.80 | $68.75 |
| IN | NU | $49.80 | $68.75 |
| KS | NU | $49.31 | $68.75 |
| KY | NU | $49.36 | $68.75 |
| LA | NU | $49.36 | $68.75 |
| MA | NU | $52.55 | $68.75 |
| MD | NU | $49.98 | $68.75 |
| ME | NU | $52.55 | $68.75 |
| MI | NU | $49.80 | $68.75 |
| MN | NU | $49.31 | $68.75 |
| MO | NU | $49.31 | $68.75 |
| MS | NU | $49.36 | $68.75 |
| MT | NU | $50.59 | $68.75 |
| NC | NU | $49.36 | $68.75 |
| ND | NU | $49.31 | $68.75 |
| NE | NU | $49.31 | $68.75 |
| NH | NU | $52.55 | $68.75 |
| NJ | NU | $49.98 | $68.75 |
| NM | NU | $49.52 | $68.75 |
| NV | NU | $50.66 | $68.75 |
| NY | NU | $49.98 | $68.75 |
| OH | NU | $49.80 | $68.75 |
| OK | NU | $49.52 | $68.75 |
| OR | NU | $50.66 | $68.75 |
| PA | NU | $49.98 | $68.75 |
| PR | NU | $76.79 | — |
| RI | NU | $52.55 | $68.75 |
| SC | NU | $49.36 | $68.75 |
| SD | NU | $49.31 | $68.75 |
| TN | NU | $49.36 | $68.75 |
| TX | NU | $49.52 | $68.75 |
| UT | NU | $50.59 | $68.75 |
| VA | NU | $49.36 | $68.75 |
| VI | NU | $68.58 | — |
| VT | NU | $52.55 | $68.75 |
| WA | NU | $50.66 | $68.75 |
| WI | NU | $49.80 | $68.75 |
| WV | NU | $49.36 | $68.75 |
| WY | NU | $50.59 | $68.75 |
How the A4604 fee compares
| Measure | Value |
|---|---|
| Rank among 13 A46 codes billed NU (lowest = 1) | 11 |
| Family fee range (average of state fees) | $2.30–$66.87 |
| Rural fee uplift | 33.1% |
Who bills A4604 (2024)
| Measure | Value |
|---|---|
| Suppliers billing rentals | — |
| Suppliers billing purchases | 4,336 |
| Referring clinicians | 126,431 |
| Medicare beneficiaries | 1,314,262 |
| States with claims | 58 |
| Share of services in top 3 states (California, Florida, Texas) | 21% |
| Year | Suppliers | Beneficiaries |
|---|---|---|
| 2022 | 4,363 | 1,120,889 |
| 2023 | 4,384 | 1,238,956 |
| 2024 | 4,336 | 1,314,262 |
Counts only. Supplier and clinician names, contact lists and state-by-state detail are in Caduvo.
Medicare utilization for A4604, 2022–2024
| Year | Services | Beneficiaries | Avg. allowed | Avg. paid |
|---|---|---|---|---|
| 2022 | 2,440,401 | 1,120,889 | $47.54 | $35.35 |
| 2023 | 2,797,243 | 1,238,956 | $51.15 | $38.24 |
| 2024 | 3,056,009 | 1,314,262 | $50.79 | $37.91 |
States with the most A4604 services (2024)
| State | Services | Avg. paid |
|---|---|---|
| California | 235,890 | $36.96 |
| Florida | 216,326 | $36.43 |
| Texas | 194,791 | $36.97 |
| Illinois | 146,762 | $37.83 |
| Pennsylvania | 127,355 | $36.67 |
NCCI unit limits (MUE)
| Claim type | Max units per day | Rationale |
|---|---|---|
| DME suppliers | 1 | Published Contractor Policy |
| outpatient hospital claims | 1 | Clinical: CMS Workgroup |
Medicare policy articles for this code
- A52467: Positive Airway Pressure (PAP) Devices for the Treatment of Obstructive Sleep Apnea - Policy Article (CGS Administrators, LLC (DME MAC) Noridian Healthcare Solutions, LLC (DME MAC)) — mentions this code in its coding guidance
- A52517: Respiratory Assist Devices - Policy Article (CGS Administrators, LLC (DME MAC) Noridian Healthcare Solutions, LLC (DME MAC)) — mentions this code in its coding guidance
Covered diagnoses (1 ICD-10-CM codes)
The diagnoses most often listed as covered in the policy articles above:
| ICD-10-CM | Diagnosis | Articles listing it |
|---|---|---|
| G47.33 | Obstructive sleep apnea (adult) (pediatric) | 1 |
What changed for A4604
- 2026-01-01: Average state fee (NU) rose 2.7%: $50.32 to $51.66
- 2006-01-01: A4604 added to HCPCS Level II
- Next scheduled CMS quarterly update (HCPCS and DMEPOS fee schedule): 2027-01-01
Frequently asked questions
What is HCPCS code A4604?
A4604 is the HCPCS Level II code for tubing with integrated heating element for use with positive airway pressure device. Short descriptor: "Tubing with heating element".
How much does Medicare pay for A4604?
Under the 2026 DMEPOS fee schedule, non-rural state fees are NU (new equipment, purchased): $49.31–$76.79. Rural fees can be higher.
Does Medicare cover A4604?
Coverage code C — Carrier judgment. Coverage is decided by the Medicare contractor (MAC) case by case.
Which diagnoses support coverage for A4604?
Medicare policy articles that cite A4604 list 1 covered ICD-10-CM diagnosis codes across 2 articles. The most cited include G47.33 (Obstructive sleep apnea (adult) (pediatric)). A listed diagnosis is necessary but not sufficient; the policy's other criteria still apply.
Did the Medicare fee for A4604 change in 2026?
The average non-rural state fee for NU moved from $50.32 in 2025 to $51.66 in 2026 (+2.7%). CMS's next quarterly HCPCS and DMEPOS update takes effect January 1, 2027.
How many units of A4604 can be billed per day?
1 on DME suppliers; 1 on outpatient hospital claims (NCCI medically unlikely edits).
Related A46 codes
- A4600 — Sleeve for intermittent limb compression device, replacement only, each
- A4601 — Lithium ion battery, rechargeable, for non-prosthetic use, replacement
- A4602 — Replacement battery for external infusion pump owned by patient, lithium, 1.5 volt, each ($5.31–$6.33)
- A4605 — Tracheal suction catheter, closed system, each ($23.31–$27.99)
- A4606 — Oxygen probe for use with oximeter device, replacement
- A4608 — Transtracheal oxygen catheter, each ($71.44–$85.73)
- A4611 — Battery, heavy duty; replacement for patient owned ventilator
- A4612 — Battery cables; replacement for patient-owned ventilator
- A4613 — Battery charger; replacement for patient-owned ventilator
- A4614 — Peak expiratory flow rate meter, hand held ($33.89–$40.68)
- A4615 — Cannula, nasal ($1.04–$1.25)
- A4616 — Tubing (oxygen), per foot ($0.08–$0.10)
Building a device that would bill under a code like this? Caduvo matches a device description to HCPCS/CPT codes, Medicare coverage and payment, and the FDA pathway in one report.
Next steps
- Run a reimbursement report for a device billed under A4604
- Watch A4604 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for A4604
Sources: CMS HCPCS Level II release October 2026; CMS DMEPOS fee schedule 2026; CMS NCCI MUE tables; CMS Medicare utilization (physician and DME supplier files); CMS Medicare Coverage Database articles. Fees are Medicare allowables, not commercial rates. Not billing or legal advice.