ICD-10-CM 2027 diagnosis code
Y21.3XXADrowning and submersion after fall into swimming pool, undetermined intent, initial encounter
Y21.3XXA is a valid, billable ICD-10-CM code for drowning and submersion after fall into swimming pool, undetermined intent, initial encounter. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.Short description: Drown after fall into swimming pool, undet intent, init
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 Y21.3XXA
Y21.3XXA is the ICD-10-CM diagnosis code for drowning and submersion after fall into swimming pool, undetermined intent, initial encounter. It belongs to category Y21 (drowning and submersion, undetermined intent), block Y21-Y33 (event of undetermined intent) and chapter 20 (external causes of morbidity). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
The 7th character "A" means initial encounter: use it while the patient is receiving active treatment for the condition.
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
It is exempt from present-on-admission (POA) reporting, so no POA indicator is required.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as E910.8 (other accidental drowning or submersion).
7th character
Ainitial encounter
Other encounter types for Y21.3:
Notes that apply from higher levels
Instructions written at a parent level also apply to Y21.3XXA.
Broader instructions also apply from Y21-Y33 Event of undetermined intent and Chapter 20: External causes of morbidity.
ICD-9-CM equivalent
Converter →- E910.8Other accidental drowning or submersionapproximate
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about Y21.3XXA
Is Y21.3XXA billable?
- Yes. Y21.3XXA is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
What does the "A" at the end of Y21.3XXA mean?
- It is the 7th character for initial encounter. Per the official guidelines, use it while the patient is receiving active treatment for the condition.
Can Y21.3XXA be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict Y21.3XXA as a principal diagnosis.
Is Y21.3XXA a CC or MCC?
- No. Y21.3XXA is neither a CC nor an MCC under MS-DRG v44.0.
What is the ICD-9 code for Y21.3XXA?
- The CMS General Equivalence Mappings map Y21.3XXA to ICD-9-CM E910.8.