A4231 HCPCS code: Infusion set for external insulin pump, needle type
A4231 is the HCPCS Level II code for infusion set for external insulin pump, needle type. Its Medicare coverage code is D (Special coverage instructions apply): Medicare covers it when its national or local coverage criteria are met. 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 | D — Special coverage instructions apply |
| Pricing indicator | 34 — DMEPOS: supplies necessary for the effective use of DME |
| BETOS category | D1E — Other durable medical equipment |
| Added | 1996-01-01 |
| Last action effective | 2000-01-01 |
NCCI unit limits (MUE)
| Claim type | Max units per day | Rationale |
|---|---|---|
| outpatient hospital claims | 1 | Clinical: CMS Workgroup |
Medicare policy articles for this code
- A52507: External Infusion Pumps - Policy Article (CGS Administrators, LLC (DME MAC) Noridian Healthcare Solutions, LLC (DME MAC)) — mentions this code in its coding guidance
Covered diagnoses (460 ICD-10-CM codes)
The diagnoses most often listed as covered in the policy articles above:
| ICD-10-CM | Diagnosis | Articles listing it |
|---|---|---|
| C91.00 | Acute lymphoblastic leukemia not having achieved remission | 1 |
| C91.01 | Acute lymphoblastic leukemia, in remission | 1 |
| C91.02 | Acute lymphoblastic leukemia, in relapse | 1 |
| D80.0 | Hereditary hypogammaglobulinemia | 1 |
| D80.2 | Selective deficiency of immunoglobulin A [IgA] | 1 |
| D80.3 | Selective deficiency of immunoglobulin G [IgG] subclasses | 1 |
| D80.4 | Selective deficiency of immunoglobulin M [IgM] | 1 |
| D80.5 | Immunodeficiency with increased immunoglobulin M [IgM] | 1 |
| D80.6 | Antibody deficiency with near-normal immunoglobulins or with hyperimmunoglobulinemia | 1 |
| D80.7 | Transient hypogammaglobulinemia of infancy | 1 |
Showing 10 of 460. The full list, non-covered diagnoses and CSV export are in Caduvo.
What changed for A4231
- 1996-01-01: A4231 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 A4231?
A4231 is the HCPCS Level II code for infusion set for external insulin pump, needle type. Short descriptor: "Infusion insulin pump needle".
Does Medicare cover A4231?
Coverage code D — Special coverage instructions apply. Medicare covers it when its national or local coverage criteria are met.
Which diagnoses support coverage for A4231?
Medicare policy articles that cite A4231 list 460 covered ICD-10-CM diagnosis codes across 1 article. The most cited include C91.00 (Acute lymphoblastic leukemia not having achieved remission), C91.01 (Acute lymphoblastic leukemia, in remission), C91.02 (Acute lymphoblastic leukemia, in relapse). A listed diagnosis is necessary but not sufficient; the policy's other criteria still apply.
How many units of A4231 can be billed per day?
1 on outpatient hospital claims (NCCI medically unlikely edits).
Related A42 codes
- A4206 — Syringe with needle, sterile, 1 cc or less, each
- A4207 — Syringe with needle, sterile 2 cc, each
- A4208 — Syringe with needle, sterile 3 cc, each
- A4209 — Syringe with needle, sterile 5 cc or greater, each
- A4210 — Needle-free injection device, each
- A4211 — Supplies for self-administered injections
- A4212 — Non-coring needle or stylet with or without catheter
- A4213 — Syringe, sterile, 20 cc or greater, each
- A4215 — Needle, sterile, any size, each
- A4216 — Sterile water, saline and/or dextrose, diluent/flush, 10 ml ($0.53–$0.99)
- A4217 — Sterile water/saline, 500 ml ($2.18–$4.93)
- A4218 — Sterile saline or water, metered dose dispenser, 10 ml
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 A4231
- Watch A4231 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for A4231
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.