ICD-10-CM code · FY2027

E66.813 Obesity, class 3

BillableValid for claims as a specific diagnosis code

About E66.813

Code: E66.813
Billable: Yes
Short description: Obesity, class 3
Category: E66 Overweight and obesity
Block: E65-E68 Overweight, obesity and other hyperalimentation
Chapter: 4 Endocrine, nutritional and metabolic diseases
Code set: FY2027, October 1, 2026 to September 30, 2027

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Coding notes for E66.813

No notes of its own; the notes below apply from the codes above it.

Also applies, from E66 Overweight and obesity

Excludes2 Not part of this condition, but a patient can have both: report both codes when both apply.

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

Code first Report the underlying condition's code before this one.

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

Use additional code Add a second code for the detail named here.

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

Chapter 4 notes (apply to every code in it)

Note

All neoplasms, whether functionally active or not, are classified in Chapter 2. Appropriate codes in this chapter (i.e. E05.8, E07.0, E16-E31, E34.-) may be used as additional codes to indicate either functional activity by neoplasms and ectopic endocrine tissue or hyperfunction and hypofunction of endocrine glands associated with neoplasms and other conditions classified elsewhere.

Excludes1 Not coded here: never report these together with this code (use the code given instead).

transitory endocrine and metabolic disorders specific to newborn (P70-P74)

Related codes in E66.81

E66.811 Obesity, class 1Billable
E66.812 Obesity, class 2Billable

Latest research on obesity

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GLP-1 receptor agonists show little effect on obesity-related cancer riskDec 8, 2025 · Chronic Disease

Landmark trials from 2MM Classics

Weekly semaglutide effective for decreasing body weight in obesity [Classics Series]Jan 1, 2025 · Gastroenterology Classics

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ICD-10-CM FY2027 code set, as published by the CDC National Center for Health Statistics (NCHS) and CMS, effective October 1, 2026 to September 30, 2027. Codes, titles and notes are shown as published. Check payer rules and the official guidelines before billing. This page is not medical advice.