E66Header code — not billable
Overweight and obesity
- Chapter
- 4. Endocrine, nutritional and metabolic diseases
- Category
- E66
- Effective date
- October 1, 2026
Related codes in category E66
E66.0Obesity due to excess caloriesE66.01Morbid (severe) obesity due to excess caloriesYesE66.09Other obesity due to excess caloriesYesE66.1Drug-induced obesityYesE66.2Morbid (severe) obesity with alveolar hypoventilationYesE66.3OverweightYesE66.8Other obesityE66.81Obesity classE66.811Obesity, class 1YesE66.812Obesity, class 2YesE66.813Obesity, class 3YesE66.89Other obesity not elsewhere classifiedYes
Frequently asked questions
What is ICD-10 code E66?
E66 is an ICD-10-CM diagnosis code for Overweight and obesity.
Is E66 a billable code?
No. E66 is a category/header code, not billable on its own — use one of its more specific child codes instead.
What ICD-10-CM chapter is E66 in?
E66 falls under Chapter 4: Endocrine, nutritional and metabolic diseases.
When did E66 become effective?
E66 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.
What other codes are related to E66?
E66 belongs to category E66, which includes 12 other codes — see the related codes list on this page.
ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.