H40.10 Unspecified open-angle glaucoma

The ICD-10-CM code for Unspecified open-angle glaucoma is H40.10 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

7: Diseases of the eye and adnexa (H00-H59)

Section

H40-H42: Glaucoma (H40-H42)

Category H40

129 codes (100 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to H40.10:

• Glaucoma › open angle

Official Coding Guidelines

Bilateral glaucoma same type/stage: use bilateral code if available

When a patient has bilateral glaucoma and both eyes are documented as being the same type and stage, and there is a code for bilateral glaucoma, report only the code for the type of glaucoma, bilateral, with the seventh character for the stage. When a patient has bilateral glaucoma and both eyes are documented as being the same type and stage, and the classification does not provide a code for bilateral glaucoma (i.e. subcategories H40.10, and H40.20)

Bilateral glaucoma with different types or stages

3) Bilateral glaucoma stage with different types or stages When a patient has bilateral glaucoma and each eye is documented as having a different type or stage, and the classification distinguishes laterality, assign the appropriate code for each eye rather than the code for bilateral glaucoma. When a patient has bilateral glaucoma and each eye is documented as having a different type, and the classification does not distinguish laterality (i.e., subcategories H40.10, and H40.20), assign one code for each type of glaucoma with the appropriate seventh character for the stage. When a patient has bilateral glaucoma and each eye is documented as having the same type, but different stage, and the classification does not distinguish laterality (i.e., subcategories H40.10 and H40.20), assign a code for the type of glaucoma for each eye with the seventh character for the specific glaucoma stage documented for each eye.

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool

Cite This Page

Reference H40.10 with the canonical source and edition:

H40.10 — Unspecified open-angle glaucoma. ICD-10 Coding Pro (ICD-10-CM FY2026). https://icd10codingpro.com/codes/H40.10

Canonical URL: https://icd10codingpro.com/codes/H40.10