L5640 — Addition to lower extremity, knee disarticulation, leather socket

HCPCS Level II L-code · short descriptor: “Knee disarticulat leather so”

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 2026-10-26; 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 2026-10-26; 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.

L5640 Medicare fee schedule (October 2026)

Base (no modifier) Prosthetics & orthotics

Medicare allowable ranges from $306.84 to $1044.94 depending on state and rural status.

Former-CBA payment limits: ceiling $1043.77 · floor $782.83

State	Non-rural	Rural
AK	$977.26	—
AL	$782.83	—
AR	$782.83	—
AZ	$949.88	—
CA	$949.88	—
CO	$1043.77	—
CT	$782.83	—
DC	$850.98	—
DE	$850.98	—
FL	$782.83	—
GA	$782.83	—
HI	$1044.94	—
IA	$818.59	—
ID	$1024.58	—
IL	$902.21	—
IN	$902.21	—
KS	$818.59	—
KY	$782.83	—
LA	$782.83	—
MA	$782.83	—
MD	$850.98	—
ME	$782.83	—
MI	$902.21	—
MN	$902.21	—
MO	$818.59	—
MS	$782.83	—
MT	$1043.77	—
NC	$782.83	—
ND	$1043.77	—
NE	$818.59	—
NH	$782.83	—
NJ	$1043.77	—
NM	$782.83	—
NV	$949.88	—
NY	$1043.77	—
OH	$902.21	—
OK	$782.83	—
OR	$1024.58	—
PA	$850.98	—
PR	$306.84	—
RI	$782.83	—
SC	$782.83	—
SD	$1043.77	—
TN	$782.83	—
TX	$782.83	—
UT	$1043.77	—
VA	$850.98	—
VI	$1043.77	—
VT	$782.83	—
WA	$1024.58	—
WI	$902.21	—
WV	$850.98	—
WY	$1043.77	—

Amounts are the Medicare DMEPOS fee-schedule allowables effective October 2026 (CMS DMEPOS Fee Schedule October 2026 (DME26-D)). Medicare typically pays 80% of the allowable after the Part B deductible; the patient owes 20%. A 2% sequestration reduction applies to the Medicare share. Former competitive-bidding-area adjustments and non-continental rates can differ — verify with your DME MAC.

Unit limit (MUE)

Medicare's Medically Unlikely Edit caps L5640 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

CO-50 medical necessity CO-151 frequency/units

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