MS-DRG · FY 2026 v43.0

MS-DRG 999 – Ungroupable

An MS-DRG in Ungrouped (Other).

✓ Official CMS v43.0 dataset
ICD-10-CM

Qualifying Diagnosis Codes

Diagnosis codes do not drive assignment for this DRG. Cases group here from the ICD-10-PCS procedure list.
ICD-10-PCS

Procedure Codes

Procedure codes do not drive assignment for this DRG.

Frequently Asked Questions

What is MS-DRG 999?

MS-DRG 999 (Ungroupable) is a medicare severity DRG in Ungrouped (Other).

← PreviousDRG 998 – Principal Diagnosis Invalid as Discharge Diagnosis
Source: CMS ICD-10 MS-DRG v43.0 Definitions Manual and the FY 2026 IPPS Final Rule (Table 5), effective October 1, 2025 through September 30, 2026. We publish the DRG assignments as CMS defines them and add the navigation, search, and code links.