A4590 — Special casting material (e.g., fiberglass)
A4590 is a HCPCS Level II code for special casting material (e.g., fiberglass). It belongs to the Transportation, Medical & Surgical Supplies, Administrative section. Medicare does not pay it — see the coverage note below before you bill it.
Medicare coverage: Not payable by Medicare
Medicare does not pay this code. It may still be valid for another payer, but a Medicare claim carrying it will not be reimbursed.
From the coverage field of the CMS Alpha-Numeric HCPCS File, release 2026Q3-Jul. This states Medicare’s position on the code, not on your particular claim.
Physician fee schedule statusI
Not valid for Medicare purposes. Medicare uses another code.
Global period: XXX
Want the dollar amount for your locality? The fee calculator applies your GPCI and the current conversion factor.
Medically Unlikely Edits — units per day
The most units of A4590 Medicare will pay on one date of service. Bill more on a single line and it is denied. The limit is not the same in every setting, so the row that matters is the one matching the claim you are building.
- practitioner
- 0 — never payable MAI 3 — Date of Service Edit: Clinical · CMS Policy
- outpatient
- 0 — never payable MAI 3 — Date of Service Edit: Clinical · CMS Policy
The adjudication indicator decides whether exceeding the limit is worth appealing at all: MAI 1 is a line edit you can support with documentation, MAI 3 is a date-of-service edit that is also appealable, and MAI 2 is absolute — no documentation overrides it. CMS MUE 2026Q3.
The CMS record for A4590
- Long descriptor
- Special casting material (e.g., fiberglass)
- Short descriptor
- Special casting material
- Added
- January 1, 1984
- BETOS
- D1A
- Pricing indicator
- 00 — Not priced by Part B
The official wording. This is what the code means.
CMS's 28-character form, which is what shows up on a remittance advice.
When CMS introduced the code.
Berenson-Eggers Type of Service — CMS's own analytic grouping.
Service not separately priced by Part B — not covered, bundled into another service, or used by Part A only.
Codes adjacent to A4590
HCPCS has no hierarchy — related items simply sit next to each other in the numbering. If A4590 is not quite right, the correct code is very often within a few positions of it.
- A4562Pessary, reusable, non rubber, any type
- A4563Rectal control system for vaginal insertion, for long term use, includes pump and all supplies and accessories, any type each
- A4564Pessary, disposable, any type
- A4565Slings
- A4566Shoulder sling or vest design, abduction restrainer, with or without swathe control, prefabricated, includes fitting and adjustment
- A4570Splint
- A4575Topical hyperbaric oxygen chamber, disposable
- A4580Cast supplies (e.g., plaster)
- A4593Neuromodulation stimulator system, adjunct to rehabilitation therapy regime, controller
- A4594Neuromodulation stimulator system, adjunct to rehabilitation therapy regime, mouthpiece each
- A4595Electrical stimulator supplies, 2 lead, per month, (e.g., tens, nmes)
- A4596Cranial electrotherapy stimulation (ces) system supplies and accessories, per month
- A4600Sleeve for intermittent limb compression device, replacement only, each
- A4601Lithium ion battery, rechargeable, for non-prosthetic use, replacement
- A4602Replacement battery for external infusion pump owned by patient, lithium, 1.5 volt, each
- A4604Tubing with integrated heating element for use with positive airway pressure device
Questions about A4590
What is HCPCS code A4590?
A4590 is a HCPCS Level II code for special casting material (e.g., fiberglass). It sits in the Transportation, Medical & Surgical Supplies, Administrative section.
Does Medicare cover A4590?
The CMS HCPCS file marks A4590 as "Not payable by Medicare". Medicare does not pay this code. It may still be valid for another payer, but a Medicare claim carrying it will not be reimbursed.
How is A4590 paid under the physician fee schedule?
A4590 carries PFS status code I. Not valid for Medicare purposes. Medicare uses another code.