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HCPCS A4575 · Level II · A code

A4575: Topical hyperbaric oxygen chamber, disposable, HCPCS Level II A code

Compiled from CMS files by the QuickIntell RCM Editorial Team · Data effective · Method: reference methodology · Report a data correction

Data currency: HCPCS Level II file: October 2026 (effective October 1, 2026); PFS relative value file: RVU26D, released August 26, 2026 (effective October 1, 2026); NCCI MUE tables: 2026 Q4 (effective October 1, 2026); NCCI PTP edits: v323r0 (2026 Q4) (effective October 1, 2026); OPPS Addendum B: October 2026 (effective October 1, 2026); Medicare Coverage Database LCD export: MCD release October 8, 2026 (effective October 4, 2026). Next CMS release: January 1, 2027 (quarterly update) for the HCPCS Level II file and NCCI MUE tables and NCCI PTP edits and OPPS Addendum B; RVU27A with the CY2027 PFS final rule, effective January 1, 2027 for the PFS relative value file; weekly, every Thursday for the Medicare Coverage Database LCD export.

Key facts for A4575

Medicare payment
no PFS amount
PFS status X; OPPS SI A: paid under another fee schedule or system
Coverage code
C
carrier judgment, so the Medicare contractor decides coverage
Practitioner MUE
0
MAI 3
OPPS status
SI A
Services not paid under OPPS; paid under fee schedule or other payment system
NCCI PTP pairs
0
practitioner file
LCDs and articles
2 / 2

TL;DR

A4575 is a Level II code from the A section (transportation, medical and surgical supplies, administrative, miscellaneous and investigational), in use since 1996: "Topical hyperbaric oxygen chamber, disposable". The physician fee schedule lists A4575 with status X (statutory exclusion: not a physician service under the fee schedule), so the PFS carries no national amount for it. Its OPPS status indicator is A, which the I/OCE table defines as "Services not paid under OPPS; paid under fee schedule or other payment system": Medicare pays A4575 under a fee schedule or payment system other than OPPS. CMS caps A4575 at practitioner 0 (MAI 3, CMS Policy); hospital outpatient 0 (MAI 3, CMS Policy); DME supplier 0 (MAI 3, CMS Policy) units per day in the 2026 Q4 MUE tables. 2 active LCDs and 2 billing and coding articles list A4575 across 10 states: L33797 (Oxygen and Oxygen Equipment), L37873 (Topical Oxygen Therapy), A56025, A56431. HCPCS record: BETOS D1A (medical/surgical supplies); pricing indicator 00; type of service 9 (other medical items or services). Nearby codes: A4565, A4562, A4558, A4557.

A4575 descriptor and code status

The October 2026 HCPCS Level II file describes A4575 as “Topical hyperbaric oxygen chamber, disposable”. It sits in the A section (transportation, medical and surgical supplies, administrative, miscellaneous and investigational), listed with the other A codes.

HCPCS file attributes of A4575
FieldValue
Short descriptorHyperbaric o2 chamber disps
Added to HCPCS1996-01-01
Last actionN (no maintenance), effective 2017-10-01
Coverage codeC: carrier judgment, so the Medicare contractor decides coverage
Pricing indicator00: not separately priced by Part B
BETOS categoryD1A: medical/surgical supplies
Type of service9: other medical items or services

Medicare payment for A4575

The physician fee schedule lists A4575 with status X (statutory exclusion: not a physician service under the fee schedule), so the PFS carries no national amount for it. Its OPPS status indicator is A, which the I/OCE table defines as "Services not paid under OPPS; paid under fee schedule or other payment system": Medicare pays A4575 under a fee schedule or payment system other than OPPS. The amounts below are national figures from the October 2026 CMS files; the contractor applies the locality, rural or state adjustment and the beneficiary's cost sharing.

Physician fee schedule (RVU26D)

Status X: statutory exclusion: not a physician service under the fee schedule. Global period XXX (global surgery concept does not apply); PC/TC indicator 9 (professional/technical concept does not apply).

Hospital outpatient (OPPS Addendum B)

Status indicator A (Services not paid under OPPS; paid under fee schedule or other payment system), with no separate OPPS payment rate.

Medically Unlikely Edits for A4575

CMS caps A4575 at practitioner 0 (MAI 3, CMS Policy); hospital outpatient 0 (MAI 3, CMS Policy); DME supplier 0 (MAI 3, CMS Policy) units per day in the 2026 Q4 MUE tables. The practitioner MUE is a date-of-service clinical edit: units above the limit deny but can be paid on appeal with documentation.

MUE values for A4575 by setting
SettingMUE (units/DOS)MAICMS rationale
Practitioner services03 Date of Service Edit: ClinicalCMS Policy
Facility outpatient hospital03 Date of Service Edit: ClinicalCMS Policy
DME supplier03 Date of Service Edit: ClinicalCMS Policy

The MUE lookup for A4575 shows every setting next to any other code on the same claim.

NCCI edits and add-on rules

No active practitioner PTP pair lists A4575 in v323r0.

A4575 is neither an add-on code nor a designated primary code in the 2026 Q4 NCCI add-on edit file.

Pair counts show exposure, not the answer for one claim. Check A4575 against a second code to see whether the pair bundles and whether a modifier can separate the services.

Medicare coverage policies for A4575

2 active Local Coverage Determinations and 2 billing and coding articles list A4575. Each applies only in its contractor's jurisdiction, and the article carries the diagnosis codes that support the item or service.

Billing and Coding Articles listing A4575
ArticleTitleContractor(s)Related LCD
A56025Billing and Coding: Topical HBO and Physician Related Service Billing and Coding GuidelinesNoridian Healthcare Solutions, LLC—
A56431Billing and Coding: Topical Oxygen TherapyPalmetto GBAL37873

Denials to expect on A4575

CARC 50 · N115

the diagnosis or documentation does not meet the LCD or billing article that lists A4575

CARC 151 · N362

units of A4575 exceed the practitioner MUE of 0 per date of service

CARC 4

the modifier reported is inconsistent with the code

CARC 16

the claim lacks information needed to adjudicate the line, such as an order, NPI or required modifier

Where QuickIntell fits for A4575 claims

QuickCode supports qualified coder review of units, modifiers and NCCI pairs for A4575 before the claim leaves, and QuickRCM carries claim readiness and the denial follow-up when an edit or coverage policy is missed.

See QuickCode for coder reviewSee QuickRCM for denial follow-upBook a meeting

Frequently asked questions: HCPCS A4575

What does HCPCS code A4575 describe?

"Topical hyperbaric oxygen chamber, disposable" (short descriptor "Hyperbaric o2 chamber disps"), in the A section (transportation, medical and surgical supplies, administrative, miscellaneous and investigational). Added 1996-01-01; last action N (no maintenance) effective 2017-10-01.

Is A4575 a CPT code?

It is not. A4575 belongs to the A section (transportation, medical and surgical supplies, administrative, miscellaneous and investigational) of HCPCS Level II, the CMS code set, not to AMA CPT.

What does Medicare pay for A4575?

The physician fee schedule lists A4575 with status X (statutory exclusion: not a physician service under the fee schedule), so the PFS carries no national amount for it. Its OPPS status indicator is A, which the I/OCE table defines as "Services not paid under OPPS; paid under fee schedule or other payment system": Medicare pays A4575 under a fee schedule or payment system other than OPPS.

How many units of A4575 can be billed per day?

CMS caps A4575 at practitioner 0 (MAI 3, CMS Policy); hospital outpatient 0 (MAI 3, CMS Policy); DME supplier 0 (MAI 3, CMS Policy) units per day in the 2026 Q4 MUE tables. For the practitioner MUE (MAI 3), units above 0 deny for the day but can be paid on appeal with documentation; denials arrive as CARC 151.

Does Medicare cover A4575?

Coverage code C (carrier judgment, so the Medicare contractor decides coverage). 2 active LCDs and 2 billing and coding articles list A4575 across 10 states: L33797 (Oxygen and Oxygen Equipment), L37873 (Topical Oxygen Therapy), A56025, A56431.

Sources

Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-10. Verify against the primary file before billing or contracting decisions. The reference methodology explains how each figure is computed from these files.

Disclaimer

This page is an operational reference compiled from CMS publications: the HCPCS Level II file, the physician, DMEPOS and clinical laboratory fee schedules, OPPS and ASC addenda, NCCI MUE, PTP and add-on edit tables and the Medicare Coverage Database. Amounts are Medicare national figures before locality and state adjustment; Medicaid and commercial payers set their own. CPT codes are shown as numbers only; CPT descriptors are copyright AMA. Nothing here is legal, clinical or billing advice.

Found a figure that does not match the CMS file? Report a data correction with the CMS file and the value you expected; the request reaches the editorial team through the contact form.