MCMCB Pro
L66

L66Cicatricial alopecia [scarring hair loss]

Non-billable headerICD-10-CM

L66 is a non-billable header ICD-10-CM code for cicatricial alopecia [scarring hair loss]. It cannot be billed on its own: choose one of the more specific child codes below.

Other codes that can never be billed with L66

These codes carry an Excludes1 note pointing at L66. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading L66 alone.

  • L43Lichen planus

Risk adjustment

L66 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead L66

7 child codes. Green means billable.

Questions about L66

Is L66 a billable ICD-10-CM code?
No. L66 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does L66 sit in the tabular list?
Diseases of the skin and subcutaneous tissue (L00-L99), in the block Disorders of skin appendages (L60-L75).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.