NPI Atlas

E66 – Overweight and obesity

ICD-10-CM 2027 diagnosis code · Overweight, obesity and other hyperalimentation

Non-billable header

ICD-10-CM code E66

Code: E66 (claims format: E66)
Description: Overweight and obesity
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 4. Endocrine, nutritional and metabolic diseases (E00-E89)
Block: E65-E68 Overweight, obesity and other hyperalimentation

Billable codes under E66

E66 is a header code and cannot be used on claims. Choose the most specific code:

E66.0 – Obesity due to excess caloriesHeader (more codes below)
E66.1 – Drug-induced obesityBillable
E66.2 – Morbid (severe) obesity with alveolar hypoventilationBillable
E66.3 – OverweightBillable
E66.8 – Other obesityHeader (more codes below)
E66.9 – Obesity, unspecifiedBillable

Notes for E66

Excludes2 (not included here):

adiposogenital dystrophy (E23.6)
lipomatosis dolorosa [Dercum] (E88.2)
lipomatosis NOS (E88.2)
Prader-Willi syndrome (Q87.11)

Code first:

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

Use additional code:

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

Frequently asked questions

What is ICD-10 code E66?

E66 is the ICD-10-CM code for overweight and obesity, in the block E65-E68 (Overweight, obesity and other hyperalimentation).

Is E66 a billable code?

No. E66 is a header code with more specific child codes; report one of the billable codes listed above.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.