A4558 — Conductive gel or paste, for use with electrical device (e.g., tens, nmes), per oz
A4558 is a HCPCS Level II code for conductive gel or paste, for use with electrical device (e.g., tens, nmes), per oz. It belongs to the Transportation, Medical & Surgical Supplies, Administrative section. Whether Medicare pays it depends on the coverage rule below.
Medicare coverage: Carrier judgment
Coverage is decided by your Medicare contractor, not by national policy. Whether this is paid depends on the LCD for your jurisdiction and on what the documentation supports.
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 statusP
Bundled or excluded. No RVUs and no payment: either bundled into another service or paid under a different provision of the Act.
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 A4558 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
- 1 unit MAI 3 — Date of Service Edit: Clinical · Clinical: Data
- DME supplier
- 0 — never payable MAI 3 — Date of Service Edit: Clinical · Published Contractor 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 A4558
- Long descriptor
- Conductive gel or paste, for use with electrical device (e.g., tens, nmes), per oz
- Short descriptor
- Conductive gel or paste
- Added
- January 1, 1985
- BETOS
- D1E
- Pricing indicator
- 34 — DMEPOS
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.
DME supplies. Price subject to floors and ceilings.
Codes adjacent to A4558
HCPCS has no hierarchy — related items simply sit next to each other in the numbering. If A4558 is not quite right, the correct code is very often within a few positions of it.
- A4544Electrode for external lower extremity nerve stimulator for restless legs syndrome
- A4545Supplies and accessories for external tibial nerve stimulator (e.g., socks, gel pads, electrodes, etc.), needed for one month
- A4550Surgical trays
- A4553Non-disposable underpads, all sizes
- A4554Disposable underpads, all sizes
- A4555Electrode/transducer for use with electrical stimulation device used for cancer treatment, replacement only
- A4556Electrodes, (e.g., apnea monitor), per pair
- A4557Lead wires, (e.g., apnea monitor), per pair
- A4559Coupling gel or paste, for use with ultrasound device, per oz
- A4560Neuromuscular electrical stimulator (nmes), disposable, replacement only
- A4561Pessary, reusable, rubber, any type
- 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
Questions about A4558
What is HCPCS code A4558?
A4558 is a HCPCS Level II code for conductive gel or paste, for use with electrical device (e.g., tens, nmes), per oz. It sits in the Transportation, Medical & Surgical Supplies, Administrative section.
Does Medicare cover A4558?
The CMS HCPCS file marks A4558 as "Carrier judgment". Coverage is decided by your Medicare contractor, not by national policy. Whether this is paid depends on the LCD for your jurisdiction and on what the documentation supports.
How is A4558 paid under the physician fee schedule?
A4558 carries PFS status code P. Bundled or excluded. No RVUs and no payment: either bundled into another service or paid under a different provision of the Act.