E66.812Obesity, class 2

E66.812 is the ICD-10-CM diagnosis code for obesity, class 2. It belongs to category E66 (Overweight and obesity), block E65-E68 (Overweight, obesity and other hyperalimentation) and chapter 4 (endocrine, nutritional and metabolic diseases). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within E66.81 (obesity class), E66.812 is specifically for obesity, class 2. Related codes cover 1 (E66.811) and 3 (E66.813).

Code first: obesity complicating pregnancy, childbirth and the puerperium, if applicable (O99.21-).

Use an additional code to identify body mass index (BMI), if known, for adults (Z68.1-Z68.45) or pediatrics (Z68.5-).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 640 (Miscellaneous Disorders of Nutrition, Metabolism, Fluids and Electrolytes with MCC, relative weight 1.3395) and DRG 641 (Miscellaneous Disorders of Nutrition, Metabolism, Fluids and Electrolytes without MCC, relative weight 0.7865), in MDC 10 (Endocrine, Nutritional and Metabolic Diseases and Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

When it is the principal diagnosis, Medicare considers it a questionable reason for an inpatient admission, so claims may be reviewed.

It was added in FY2025, effective October 1, 2024.