L40.9 ICD-10-CM Code: Psoriasis, unspecified
HCC Buddy Code Card
Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.
FY 2026 Apr update / Diseases of the skin and subcutaneous tissue (L00-L99) / Papulosquamous disorders (L40-L45)
L40.9
Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidancePsoriasis, unspecified
Psoriasis without specification of the type or form; used when the specific presentation is not documented or identified.
Buddy Insight
This unspecified psoriasis code represents incomplete documentation where the type of psoriasis is not identified.
CMS-HCC V28
00
RAF 0
CMS-HCC V24
00
RAF 0
ACA/HHS
00
RAF 0
ESRD/PACE
00
RAF 0
RXHCC
MappedHCC 316
RAF 0.0
Code Trumping
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Code Book Path
Inclusion Terms
OfficialICD-10-CM does not list inclusion terms for L40.9 in this effective period.
Excludes 2
OfficialICD-10-CM does not list Excludes 2 notes for L40.9 in this effective period.
Related Child Codes
Includes
OfficialICD-10-CM does not list Includes notes for L40.9 in this effective period.
Excludes 1
OfficialICD-10-CM does not list Excludes 1 notes for L40.9 in this effective period.
Code First
OfficialICD-10-CM does not list Code First sequencing instructions for L40.9 in this effective period.
Use Additional
OfficialICD-10-CM does not list Use Additional Code instructions for L40.9 in this effective period.
Code Also
OfficialICD-10-CM does not list Code Also instructions for L40.9 in this effective period.
Buddy Documentation Tip
MEAT Support
Audit Caution
Common Mistakes
Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.
Is L40.9 an HCC code?
No. L40.9 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for L40.9
For L40.9to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed L40.9 during that encounter, not just copy-forwarded from a problem list.
What This Code Means
L40.9 is the ICD-10-CM diagnosis code for psoriasis, unspecified. Psoriasis without specification of the type or form; used when the specific presentation is not documented or identified. L40.9 sits in the ICD-10-CM chapter for diseases of the skin and subcutaneous tissue (l00-l99), within the section covering papulosquamous disorders (l40-l45).
L40.9 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.
Does not map to any CMS-HCC in V28, V24, or ESRD models. Maps only to RxHCC 316 (Psoriasis and Other Papulosquamous Disorders) for prescription drug risk adjustment. Querying for specificity could identify psoriatic arthritis which maps to high-value HCCs. Coders reviewing L40.9 should check whether additional documentation would support a more specific child code in the same hierarchy that does map to a payment HCC, capturing the correct specificity is the highest-impact RAF improvement available within accurate coding.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for L40.9 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This is a non-specific code; attempt to obtain more detailed clinical information to assign a more specific L40 code
- •Query the provider if the psoriasis type (plaque, guttate, pustular, etc.) can be determined from the clinical presentation
Clinical Significance
This unspecified psoriasis code represents incomplete documentation where the type of psoriasis is not identified. Given that psoriasis affects treatment decisions, risk adjustment, and comorbidity screening, specifying the type improves both coding accuracy and clinical care. This code should prompt a query for more specific documentation.
Documentation Requirements
- ✓Provider documentation of psoriasis diagnosis
- ✓Any description of morphology or distribution
- ✓Current treatment plan
- ✓Evidence the condition was evaluated during the encounter
- ✓Query opportunity: ask the provider to specify the psoriasis type
Commonly Confused Codes
- •L40.0 (Psoriasis vulgaris) — the most common type; use when plaque psoriasis is documented
- •L40.4 (Guttate psoriasis) — use when small droplet-shaped lesions are described
- •L40.8 (Other psoriasis) — use when a specific non-plaque variant is identified
- •L40.50 (Arthropathic psoriasis, unspecified) — use when joint involvement is also present