ICD-10-CM 2027 diagnosis code
E66.81Obesity class
E66.81 is a header code, so it can't be reported by itself. Choose one of the 3 more specific codes beneath it.
Code last changed in FY2025 (effective October 1, 2024). Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About E66.81
E66.81 is the ICD-10-CM diagnosis code for obesity class. 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 a header code, so it can't be reported by itself; one of its 3 subcodes must be used instead.
Within E66.8 (other obesity), E66.81 is specifically for obesity class. Related codes cover not elsewhere classified (E66.89).
To report this condition, pick the subcode that matches the documentation: E66.811 (1), E66.812 (2) and E66.813 (3).
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 was added in FY2025, effective October 1, 2024.
Specific codes under E66.81
Notes that apply from higher levels
Instructions written at a parent level also apply to E66.81.
› From E66 Overweight and obesity
- obesity complicating pregnancy, childbirth and the puerperium, if applicable (O99.21-)
Broader instructions also apply from Chapter 4: Endocrine, nutritional and metabolic diseases.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2025 (effective 10/1/2024): Added
- No changes since FY2025.
Common questions about E66.81
Is E66.81 billable?
- No. E66.81 is a header code. Report one of its more specific subcodes instead.