ICD-10 Code for Obesity

The default ICD-10-CM 2027 code for obesity is E66.9 – Obesity, unspecified. More specific codes depend on the details documented, as listed in the official index (16 codes, 15 billable).

Main code: E66.9 – Obesity, unspecified
Billable: Yes

Index entries for Obesity

with alveolar hypoventilation – E66.2
adrenal – E27.8
class
- 1 – E66.811
- 2 – E66.812
- 3 – E66.813
complicating
- childbirth – O99.214
- pregnancy – O99.21- (header)
- puerperium – O99.215
constitutional – E66.89
dietary counseling and surveillance – Z71.3
drug-induced – E66.1
due to
- disruption of MC4R pathway – E88.82
- drug – E66.1
- excess calories – E66.09
  - morbid – E66.01
  - severe – E66.01
- gene mutation
  - leptin (LEP) – E88.82
  - leptin receptor (LEPR) – E88.82
  - melanocortin 4 Receptor (MC4R) – E88.82
  - nuclear receptor coactivator 1 (NCOA1) – E88.82
  - proopiomelanocortin (POMC) – E88.82
  - proprotein convertase subtilisin/kexin type 1 (PCSK1) – E88.82
  - src homology 2B adaptor signaling protein (SH2B1) – E88.82
endocrine – E66.89
endogenous – E66.89
exogenous – E66.09
familial – E66.89
glandular – E66.89
hypothyroid – see Hypothyroidism
hypoventilation syndrome (OHS) – E66.2
morbid – E66.01
- with
  - alveolar hypoventilation – E66.2
  - obesity hypoventilation syndrome (OHS) – E66.2
- due to excess calories – E66.01
nutritional – E66.09
pituitary – E23.6
severe – E66.01
specified type NEC – E66.89

How to choose the right code

Start with the main term, then pick the indented subterm that matches the documentation (type, cause, site, laterality, episode of care). Always confirm the code in the tabular list: follow its Excludes1/Excludes2, “code first” and “use additional code” notes, and add a 7th character where required.

Source: CDC/NCHS ICD-10-CM FY2027 alphabetic index.