L1831 — Knee orthosis, locking knee joint(s), positional orthosis, prefabricated, includes fitting and adjustment
HCPCS Level II L-code · short descriptor: “Knee orth pos locking joint”
- Code system
- HCPCS Level II
- Family
- L — Orthotics & prosthetics
- Medicare coverage status
- Carrier judgment — coverage decided by the DME MAC
- DMEPOS payment category
- Prosthetics & orthotics
- Prior authorization
- Not on Medicare required-PA list
- Face-to-face & WOPD
- Not on the required list
- MUE unit limit
- 2
- Status
- Active (HCPCS Level II October 2026)
Prior authorization
Not on the Medicare required-PA list (CMS Required Prior Authorization List — 74 items in force on 2026-10-25; 8 more from 2026-10-28; sources: CMS list updated 2026-01-13, CMS-6109-N (91 FR 47972)). Medicare Advantage and commercial plans set their own prior-authorization rules for this code — verify per plan before delivery.
Order readiness — what the written order must contain
Every Medicare DMEPOS claim needs a Standard Written Order with all six elements (42 CFR 410.38(d)):
- Beneficiary name or Medicare Beneficiary Identifier (MBI) (42 CFR 410.38(d)(1)(i)(A))
- General description of the item (42 CFR 410.38(d)(1)(i)(B))
- Quantity to be dispensed, if applicable (42 CFR 410.38(d)(1)(i)(C))
- Order date (42 CFR 410.38(d)(1)(i)(D))
- Treating practitioner name or NPI (42 CFR 410.38(d)(1)(i)(E))
- Treating practitioner signature (42 CFR 410.38(d)(1)(i)(F))
Not on the F2F/WOPD list (CMS Required F2F & WOPD List — 83 items in force on 2026-10-25; 22 more from 2026-10-28; sources: CMS list effective 2026-04-13 (91 FR 1250), CMS-6109-N (91 FR 47972)). The standard written order must reach the supplier before claim submission.
Blank requirements checklist only — MyMedi-AI never collects or stores completed orders.
L1831 Medicare fee schedule (October 2026)
Base (no modifier) Prosthetics & orthotics
Medicare allowable ranges from $353.04 to $388.33 depending on state and rural status.
Former-CBA payment limits: ceiling $430.82 · floor $323.12
| State | Non-rural | Rural |
|---|---|---|
| AK | $353.04 | — |
| AL | $363.64 | — |
| AR | $363.62 | — |
| AZ | $353.04 | — |
| CA | $353.04 | — |
| CO | $365.67 | — |
| CT | $353.04 | — |
| DC | $353.04 | — |
| DE | $353.04 | — |
| FL | $363.64 | — |
| GA | $363.64 | — |
| HI | $353.04 | — |
| IA | $359.92 | — |
| ID | $353.04 | — |
| IL | $361.70 | — |
| IN | $361.70 | — |
| KS | $359.92 | — |
| KY | $363.64 | — |
| LA | $363.62 | — |
| MA | $353.04 | — |
| MD | $353.04 | — |
| ME | $353.04 | — |
| MI | $361.70 | — |
| MN | $361.70 | — |
| MO | $359.92 | — |
| MS | $363.64 | — |
| MT | $365.67 | — |
| NC | $363.64 | — |
| ND | $365.67 | — |
| NE | $359.92 | — |
| NH | $353.04 | — |
| NJ | $353.04 | — |
| NM | $363.62 | — |
| NV | $353.04 | — |
| NY | $353.04 | — |
| OH | $361.70 | — |
| OK | $363.62 | — |
| OR | $353.04 | — |
| PA | $353.04 | — |
| PR | $388.33 | — |
| RI | $353.04 | — |
| SC | $363.64 | — |
| SD | $365.67 | — |
| TN | $363.64 | — |
| TX | $363.62 | — |
| UT | $365.67 | — |
| VA | $353.04 | — |
| VI | $388.33 | — |
| VT | $353.04 | — |
| WA | $353.04 | — |
| WI | $361.70 | — |
| WV | $353.04 | — |
| WY | $365.67 | — |
Unit limit (MUE)
Medicare's Medically Unlikely Edit caps L1831 at 2 units per date of service (absolute). Units above the MUE deny — typically as CO-151. Rationale: Anatomic Consideration.
Common denial codes to watch
Related L-codes
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