Is E66.01 a billable ICD-10-CM code?

Yes. E66.01 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does E66.01 sit in the tabular list?

Endocrine, nutritional and metabolic diseases (E00-E89), in the block Overweight, obesity and other hyperalimentation (E65-E68).

What cannot be coded together with E66.01?

E66.01 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

E66.01

E66.01 — Morbid (severe) obesity due to excess calories

Billable / specific codeICD-10-CM

E66.01 is a billable, specific ICD-10-CM code for morbid (severe) obesity due to excess calories. It is valid for submission on a claim.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

morbid (severe) obesity with alveolar hypoventilation (E66.2)

Risk adjustment

E66.01 risk-adjusts. Under the CMS-HCC V28 model it maps to this category:

HCC 48 Morbid Obesity0.186 RAF

Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score.

Medicare coverage

E66.01 is named in 10 Medicare coverage policies — 10 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A52447Laparoscopic Sleeve Gastrectomy (LSG) – Medical Policy Article
A54923Billing and Coding: Bariatric Surgery for Treatment of Co-Morbidities Conditions Related to Morbid Obesity
A56852Billing and Coding: Laparoscopic Sleeve Gastrectomy for Severe Obesity
A57065Billing and Coding: Outpatient Psychiatry and Psychology Services

How E66.01 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to E66.01.

Obesity›morbid
Obesity›severe
Obesity›morbid›due to excess calories
Obesity›due to›excess calories›morbid
Obesity›due to›excess calories›severe

Related codes at this level

Codes that share E66.0. If E66.01 is not quite right, the correct code is usually one of these.

E66.09Other obesity due to excess calories

Questions about E66.01

Is E66.01 a billable ICD-10-CM code?: Yes. E66.01 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does E66.01 sit in the tabular list?: Endocrine, nutritional and metabolic diseases (E00-E89), in the block Overweight, obesity and other hyperalimentation (E65-E68).
What cannot be coded together with E66.01?: E66.01 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.