ICD-10 · PDGM grouping
Y21 Drowning and submersion, undetermined intent
All 21 codes in the Y21 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
ICD-10-CM FY2027 · CMS grouper v07.2.26
Codes in family
21
Can lead a claim
0
Cannot lead a claim
21
What CMS assigns to Y21
None of the 21 codes is assigned a clinical group. None of the 21 is assigned a comorbidity subgroup. None can lead a claim.
Every code in Y21
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| Y21.0 Drowning and submersion while in bathtub, undetermined intent | ||||
| Y21.0XXA | Drowning and submersion while in bathtub, undetermined intent, initial encounterCMS: Drown while in bathtub, undetermined intent, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.0XXD | Drowning and submersion while in bathtub, undetermined intent, subsequent encounterCMS: Drown while in bathtub, undetermined intent, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.0XXS | Drowning and submersion while in bathtub, undetermined intent, sequelaCMS: Drown while in bathtub, undetermined intent, sequela | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.1 Drowning and submersion after fall into bathtub, undetermined intent | ||||
| Y21.1XXA | Drowning and submersion after fall into bathtub, undetermined intent, initial encounterCMS: Drown after fall into bathtub, undetermined intent, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.1XXD | Drowning and submersion after fall into bathtub, undetermined intent, subsequent encounterCMS: Drown after fall into bathtub, undetermined intent, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.1XXS | Drowning and submersion after fall into bathtub, undetermined intent, sequelaCMS: Drown after fall into bathtub, undetermined intent, sequela | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.2 Drowning and submersion while in swimming pool, undetermined intent | ||||
| Y21.2XXA | Drowning and submersion while in swimming pool, undetermined intent, initial encounterCMS: Drown while in swimming pool, undetermined intent, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.2XXD | Drowning and submersion while in swimming pool, undetermined intent, subsequent encounterCMS: Drown while in swimming pool, undetermined intent, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.2XXS | Drowning and submersion while in swimming pool, undetermined intent, sequelaCMS: Drown while in swimming pool, undetermined intent, sequela | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.3 Drowning and submersion after fall into swimming pool, undetermined intent | ||||
| Y21.3XXA | Drowning and submersion after fall into swimming pool, undetermined intent, initial encounterCMS: Drown after fall into swimming pool, undet intent, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.3XXD | Drowning and submersion after fall into swimming pool, undetermined intent, subsequent encounterCMS: Drown after fall into swimming pool, undet intent, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.3XXS | Drowning and submersion after fall into swimming pool, undetermined intent, sequelaCMS: Drown after fall into swimming pool, undet intent, sequela | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.4 Drowning and submersion in natural water, undetermined intent | ||||
| Y21.4XXA | Drowning and submersion in natural water, undetermined intent, initial encounterCMS: Drown in natural water, undetermined intent, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.4XXD | Drowning and submersion in natural water, undetermined intent, subsequent encounterCMS: Drown in natural water, undetermined intent, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.4XXS | Drowning and submersion in natural water, undetermined intent, sequelaCMS: Drown in natural water, undetermined intent, sequela | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.8 Other drowning and submersion, undetermined intent | ||||
| Y21.8XXA | Other drowning and submersion, undetermined intent, initial encounterCMS: Oth drowning and submersion, undetermined intent, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.8XXD | Other drowning and submersion, undetermined intent, subsequent encounterCMS: Oth drowning and submersion, undetermined intent, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.8XXS | Other drowning and submersion, undetermined intent, sequela | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.9 Unspecified drowning and submersion, undetermined intent | ||||
| Y21.9XXA | Unspecified drowning and submersion, undetermined intent, initial encounterCMS: Unsp drowning and submersion, undetermined intent, init | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.9XXD | Unspecified drowning and submersion, undetermined intent, subsequent encounterCMS: Unsp drowning and submersion, undetermined intent, subs | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
| Y21.9XXS | Unspecified drowning and submersion, undetermined intent, sequelaCMS: Unsp drowning and submersion, undetermined intent, sequela | Cannot lead a claimExternal cause of injury code not reportable as principal diagnosis | None | None |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
The monthly home health regs digest
What CMS changed, what's due next, and what to do about it — one email a month, no fluff. Read the first issue