ICD-10 R63.6
Billable / SpecificUnderweight
About ICD-10-CM R63.6
ICD-10-CM code R63.6 represents Underweight. This is a billable/specific code in the Symptoms, Signs, and Abnormal Findings chapter (block R63). The 2026 edition of ICD-10-CM R63.6 became effective on October 1, 2025.
Type 1 Excludes
Pure excludes, these codes can never be coded together with R63.6. The conditions are mutually exclusive (e.g., congenital vs acquired forms).
- abnormal weight loss (R63.4)
- anorexia nervosa (F50.0-)
- malnutrition (E40-E46)
Use Additional Code
When coding R63.6, also report these additional codes when applicable.
- code to identify body mass index (BMI), if known (Z68.-)
Medicare LCD Coverage for R63.6
Local Coverage Determinations (LCDs) from CMS MACs that list R63.6 as a covered diagnosis.
Showing top 10 of 22 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing R63.6.
2 Medicare
CPT Codes Commonly Billed with R63.6
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
We don't have CPT pairings indexed for this specific code yet. Use the CPT search above to find common procedures, or check your payer's published medical policy for code-specific guidance.
Convert R63.6 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| R63.6 | 78322 | 00000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To R63.6
Other codes in section R50-R69 (General symptoms and signs).
ICD-10 R63.6, Billing FAQ
Is ICD-10 code R63.6 billable? +
Yes, R63.6 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What codes are Type 1 Excludes for R63.6? +
Type 1 Excludes (never code together with R63.6): abnormal weight loss (R63.4); anorexia nervosa (F50.0-); malnutrition (E40-E46)
What ICD-9 codes does R63.6 map to? +
Per CMS GEMs, R63.6 maps to ICD-9 codes: 78322. Useful for legacy data review and historical claim analysis.
Get the full PayerReady toolkit
Free access to CPT/ICD-10 lookup, denial appeals, fee comparator, and claim auditing with credentialing enrollment.
Start free →Run this code through our claim audit tool
Check NCCI bundling, MUE limits, and modifier logic before submission.
Try the auditor →Did this page help?
Quick signal so we know what to improve.
If you want a code reference page that doesn't exist yet, email coding@payerready.com.
Tell us what's missing or wrong: coding@payerready.com. We respond within 5 business days.
Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on May 31, 2026.
Powered by 11K CPT · 98K ICD-10 · 860K MPFS rates · 4.5M NCCI edits · 9.5M NPIs. Our data methodology · About our coding team