What is the ICD-10 code for glaucoma?

The ICD-10-CM code for glaucoma is H40.9 when documented without further specification. More specific documentation changes the code — see the scenario table.

Yes — H40.9 is a billable ICD-10-CM code, but payers expect the most specific code the documentation supports.

ICD-10 Code for glaucoma

The ICD-10-CM code for glaucoma is H40.9 when documented without further specification. RxHCC Glaucoma codes in category H40. H40.9 is unspecified glaucoma - the least specific option. Glaucoma suspect (preglaucoma, H40.00-) is a distinct, lower-acuity state with its own laterality codes. Documentation of glaucoma type, stage, and eye drives a more specific H40 code.

H40.9 is a risk-adjusting diagnosis under RxHCC models. Create a free account to see model versions, RAF contribution, and AI-powered HCC suppression analysis.

Create your free account →

Symptom code vs. confirmed diagnosis

H40.9 is a confirmed-diagnosis code for documented glaucoma, not a symptom code, but it is unspecified. Documentation distinguishing established glaucoma from glaucoma suspect (preglaucoma, H40.0-), and the eye involved, moves the coder off H40.9.

Which Code Should You Use?

H40.9 ✓ Billable — Unspecified glaucoma

Unspecified glaucoma (type, stage, and eye not specified).

H40.001 ✓ Billable — Preglaucoma, unspecified, right eye

Preglaucoma (glaucoma suspect), unspecified, right eye.

H40.002 ✓ Billable — Preglaucoma, unspecified, left eye

Preglaucoma (glaucoma suspect), unspecified, left eye.

H40.003 ✓ Billable — Preglaucoma, unspecified, bilateral

Preglaucoma (glaucoma suspect), unspecified, bilateral.

What to Document

Whether the finding is established glaucoma versus glaucoma suspect / preglaucoma (H40.0-), which are distinct.
The glaucoma type (e.g., open-angle, angle-closure) and, for open-angle, the stage - each drives a more specific H40 code.
Laterality - right, left, or bilateral eye.

Common Documentation Pitfalls

Glaucoma suspect (preglaucoma, H40.0-) is not established glaucoma - use the suspect codes only when that is what is documented.
Do not leave glaucoma at the unspecified H40.9 when the type, stage, and eye are documented.

Also Known As

Official ICD-10-CM Alphabetic Index terms that point to H40.9:

Glaucoma

Coding Notes

H40.9 is unspecified glaucoma. Glaucoma suspect (preglaucoma) codes to H40.0- with its own laterality (H40.001 right, H40.002 left, H40.003 bilateral). Documented glaucoma type, stage, and eye yield a more specific H40 code, so the unspecified default should be uncommon.