Obesity ICD-10-CM Codes
ICD-10-CM codes for overweight and obesity, including morbid (severe) obesity and obesity with alveolar hypoventilation.
Coding Guidance for Obesity
Category E66 includes E66.01 (morbid obesity due to excess calories), E66.2 (morbid obesity with alveolar hypoventilation, also called obesity hypoventilation syndrome), and E66.9 (obesity, unspecified).
Always add a BMI code from category Z68 when the BMI is documented. BMI may be taken from any clinician's documentation (such as nursing notes), but the obesity diagnosis itself must come from the provider.
Obesity is always clinically significant and reportable when documented, per Coding Clinic guidance, even without active treatment during the encounter.
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About these codes
These ICD-10-CM codes are sourced from the official FY2026 tabular list published by the Centers for Medicare & Medicaid Services (CMS), effective April 1, 2026. Click any code for full clinical details including instructional notes, excludes guidance, and DRG mappings.
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