L1820 — Knee orthosis, elastic with condylar pads and joints, with or without patellar control, prefabricated item that has been trimmed, bent, molded, assembled, or otherwise customized to fit a specific patient by an individual with expertise
L1820 is a HCPCS Level II code for knee orthosis, elastic with condylar pads and joints, with or without patellar control, prefabricated item that has been trimmed, bent, molded, assembled, or otherwise customized to fit a specific patient by an individual with expertise. It belongs to the Orthotic and Prosthetic Procedures and Devices 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.
Medically Unlikely Edits — units per day
The most units of L1820 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
- 2 units MAI 2 — Date of Service Edit: Policy · Anatomic Consideration
- DME supplier
- 2 units MAI 2 — Date of Service Edit: Policy · Anatomic Consideration
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 L1820
- Long descriptor
- Knee orthosis, elastic with condylar pads and joints, with or without patellar control, prefabricated item that has been trimmed, bent, molded, assembled, or otherwise customized to fit a specific patient by an individual with expertise
- Short descriptor
- Ko elas w/ condyle pads & jo
- Added
- January 1, 1986
- BETOS
- D1F
- Pricing indicator
- 38 — 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.
Orthotics, prosthetics, prosthetic devices and vision services. Price subject to floors and ceilings.
Codes adjacent to L1820
HCPCS has no hierarchy — related items simply sit next to each other in the numbering. If L1820 is not quite right, the correct code is very often within a few positions of it.
- L1690Combination, bilateral, lumbo-sacral, hip, femur orthosis providing adduction and internal rotation control, prefabricated, includes fitting and adjustment
- L1700Legg perthes orthosis, (toronto type), custom fabricated
- L1710Legg perthes orthosis, (newington type), custom fabricated
- L1720Legg perthes orthosis, trilateral, (tachdijan type), custom fabricated
- L1730Legg perthes orthosis, (scottish rite type), custom fabricated
- L1755Legg perthes orthosis, (patten bottom type), custom fabricated
- L1810Knee orthosis, elastic with joints, prefabricated item that has been trimmed, bent, molded, assembled, or otherwise customized to fit a specific patient by an individual with expertise
- L1812Knee orthosis, elastic with joints, prefabricated, off-the-shelf
- L1821Knee orthosis, elastic with condylar pads and joints, with or without patellar control, prefabricated, off the shelf
- L1830Knee orthosis, immobilizer, canvas longitudinal, prefabricated, off-the-shelf
- L1831Knee orthosis, locking knee joint(s), positional orthosis, prefabricated, includes fitting and adjustment
- L1832Knee orthosis, adjustable knee joints (unicentric or polycentric), positional orthosis, rigid support, prefabricated item that has been trimmed, bent, molded, assembled, or otherwise customized to fit a specific patient by an individual with expertise
- L1833Knee orthosis, adjustable knee joints (unicentric or polycentric), positional orthosis, rigid support, prefabricated, off-the shelf
- L1834Knee orthosis, without knee joint, rigid, custom fabricated
- L1836Knee orthosis, rigid, without joint(s), includes soft interface material, prefabricated, off-the-shelf
- L1840Knee orthosis, derotation, medial-lateral, anterior cruciate ligament, custom fabricated
Questions about L1820
What is HCPCS code L1820?
L1820 is a HCPCS Level II code for knee orthosis, elastic with condylar pads and joints, with or without patellar control, prefabricated item that has been trimmed, bent, molded, assembled, or otherwise customized to fit a specific patient by an individual with expertise. It sits in the Orthotic and Prosthetic Procedures and Devices section.
Does Medicare cover L1820?
The CMS HCPCS file marks L1820 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.