ICD-10-CM 2027 diagnosis code

H00.01Hordeolum externum

Not billable — use a more specific code

H00.01 is a header code, so it can't be reported by itself. Choose one of the 7 more specific codes beneath it.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About H00.01

H00.01 is the ICD-10-CM diagnosis code for Hordeolum externum. It belongs to category H00 (Hordeolum and chalazion), block H00-H05 (disorders of eyelid, lacrimal system and orbit) and chapter 7 (diseases of the eye and adnexa). It is a header code, so it can't be reported by itself; one of its 7 subcodes must be used instead.

Within H00.0 (Hordeolum (externum) (internum) of eyelid), H00.01 is specifically for Hordeolum externum. Related codes cover Hordeolum internum (H00.02) and abscess of eyelid (H00.03).

To report this condition, pick the subcode that matches the documentation: H00.011 (right upper eyelid), H00.012 (right lower eyelid), H00.013 (right eye, unspecified eyelid), H00.014 (left upper eyelid), H00.015 (left lower eyelid), H00.016 (left eye, unspecified eyelid) and H00.019 (unspecified eye, unspecified eyelid).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Specific codes under H00.01

Coding notes

Applicable toConditions and synonyms classified to this code

Hordeolum NOS
Stye

Notes that apply from higher levels

Instructions written at a parent level also apply to H00.01.

Broader instructions also apply from H00-H05 Disorders of eyelid, lacrimal system and orbit and Chapter 7: Diseases of the eye and adnexa.

Code history

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2027

FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
No changes since FY2016.

Common questions about H00.01

Is H00.01 billable?: No. H00.01 is a header code. Report one of its more specific subcodes instead.