A4420 HCPCS code: Ostomy pouch, closed; for use on barrier with locking flange (2 piece), each
A4420 is the HCPCS Level II code for ostomy pouch, closed; for use on barrier with locking flange (2 piece), each. 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 outpatient hospital claims.
Code details
| Field | Value |
|---|---|
| Section | A codes — Transportation, medical/surgical supplies and miscellaneous |
| Coverage code | C — Carrier judgment |
| Pricing indicator | 37 — DMEPOS: ostomy, tracheostomy and urological supplies |
| BETOS category | D1F — Prosthetic and orthotic devices |
| Added | 2004-01-01 |
| Last action effective | 2004-01-01 |
NCCI unit limits (MUE)
| Claim type | Max units per day | Rationale |
|---|---|---|
| outpatient hospital claims | 1 | Clinical: CMS Workgroup |
| practitioner claims | 1 | Clinical: CMS Workgroup |
Medicare policy articles for this code
- A52487: Ostomy Supplies - Policy Article (CGS Administrators, LLC (DME MAC) Noridian Healthcare Solutions, LLC (DME MAC)) — mentions this code in its coding guidance
Covered diagnoses (10 ICD-10-CM codes)
The diagnoses most often listed as covered in the policy articles above:
| ICD-10-CM | Diagnosis | Articles listing it |
|---|---|---|
| K94.00 | Colostomy complication, unspecified | 1 |
| K94.03 | Colostomy malfunction | 1 |
| K94.10 | Enterostomy complication, unspecified | 1 |
| K94.13 | Enterostomy malfunction | 1 |
| Z43.2 | Encounter for attention to ileostomy | 1 |
| Z43.3 | Encounter for attention to colostomy | 1 |
| Z43.6 | Encounter for attention to other artificial openings of urinary tract | 1 |
| Z93.2 | Ileostomy status | 1 |
| Z93.3 | Colostomy status | 1 |
| Z93.6 | Other artificial openings of urinary tract status | 1 |
What changed for A4420
- 2004-01-01: A4420 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 A4420?
A4420 is the HCPCS Level II code for ostomy pouch, closed; for use on barrier with locking flange (2 piece), each. Short descriptor: "Ost pch clsd for bar w lk fl".
Does Medicare cover A4420?
Coverage code C — Carrier judgment. Coverage is decided by the Medicare contractor (MAC) case by case.
Which diagnoses support coverage for A4420?
Medicare policy articles that cite A4420 list 10 covered ICD-10-CM diagnosis codes across 1 article. The most cited include K94.00 (Colostomy complication, unspecified), K94.03 (Colostomy malfunction), K94.10 (Enterostomy complication, unspecified). A listed diagnosis is necessary but not sufficient; the policy's other criteria still apply.
How many units of A4420 can be billed per day?
1 on outpatient hospital claims; 1 on practitioner claims (NCCI medically unlikely edits).
Related A44 codes
- A4400 — Ostomy irrigation set ($59.20–$90.97)
- A4402 — Lubricant, per ounce ($1.93–$5.70)
- A4404 — Ostomy ring, each ($2.03–$2.60)
- A4405 — Ostomy skin barrier, non-pectin based, paste, per ounce ($4.87–$5.76)
- A4406 — Ostomy skin barrier, pectin-based, paste, per ounce ($8.16–$9.78)
- A4407 — Ostomy skin barrier, with flange (solid, flexible, or accordion), extended wear, with built-in convexity, 4 x 4 inches or smaller, each ($12.48–$14.94)
- A4408 — Ostomy skin barrier, with flange (solid, flexible or accordion), extended wear, with built-in convexity, larger than 4 x 4 inches, each ($14.07–$16.87)
- A4409 — Ostomy skin barrier, with flange (solid, flexible or accordion), extended wear, without built-in convexity, 4 x 4 inches or smaller, each ($8.84–$10.60)
- A4410 — Ostomy skin barrier, with flange (solid, flexible or accordion), extended wear, without built-in convexity, larger than 4 x 4 inches, each ($12.88–$15.43)
- A4411 — Ostomy skin barrier, solid 4 x 4 or equivalent, extended wear, with built-in convexity, each ($7.26–$8.70)
- A4412 — Ostomy pouch, drainable, high output, for use on a barrier with flange (2 piece system), without filter, each ($3.86–$4.56)
- A4413 — Ostomy pouch, drainable, high output, for use on a barrier with flange (2 piece system), with filter, each ($7.85–$9.44)
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Next steps
- Run a reimbursement report for a device billed under A4420
- Watch A4420 for fee, coverage and descriptor changes
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Sources: CMS HCPCS Level II release October 2025; CMS DMEPOS fee schedule; 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.