2027 ICD-10-CM Diagnosis Code T69.021AImmersion foot, right foot, initial encounter

ICD-10-CM Codes›S00–T88›T66-T78›T69

ICD-10-CM T69.021A
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

T69.021A is a billable ICD-10-CM diagnosis code for immersion foot, right foot, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 922 through 923. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 29 closely related codes. Coders also document this condition as immersion foot. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Effect of other external causes, initial encounter.

Code Identity

ICD-10-CM Code
T69.021A
Billable Status
Yes — Valid for Submission
Code Describes
Immersion foot, right foot, initial encounter
Short Description
Immersion foot, right foot, initial encounter
Same as the full description in the CMS dataset.
Parent Code
T69.021
Immersion foot, right foot

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionT66-T78Other and unspecified effects of external causes
CategoryT69Other effects of reduced temperature
This CodeT69.021AImmersion foot, right foot, initial encounter

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Immersion foot
  • Right trench foot

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Other effects of reduced temperature (T69). Use the following options for the applicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027, published by CMS and the National Center for Health Statistics.

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to T69.021A: its own notes plus those printed at T69, block T66-T78, and Chapter 19. A note printed at a category, block or chapter applies to every code under it.

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From T69 Other effects of reduced temperature applies to 27 codes
From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From T69 Other effects of reduced temperature applies to 27 codes
  • code to identify source of exposure:
  • Exposure to excessive cold of man-made origin (W93)
  • Exposure to excessive cold of natural origin (X31)
From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes
  • code to identify any retained foreign body, if applicable (Z18.-)

Code Also

A second code may be needed to fully describe the condition; the note gives no sequencing direction.

From Block T66-T78 Other and unspecified effects of external causes applies to 456 codes
  • if applicable, place of occurrence, such as:
  • highway rest stop (Y92.523)
  • school (private) (public) (state) as the place of occurrence of the external cause (Y92.21-)
  • service areas as the place of occurrence of the external cause (Y92.52-)
  • single-family non-institutional (private) house as the place of occurrence of the external cause (Y92.01-)
  • transport vehicle as the place of occurrence of the external cause (Y92.81-)

Notes

General instructions on how these codes are used.

From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes
  • Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
  • The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.

7th Character

Every code in the category takes a 7th character from the listed values, with the placeholder X filling any empty positions before it.

From T69 Other effects of reduced temperature applies to 27 codes
  • The appropriate 7th character is to be added to each code from category T69
Values for category T69 Encounter: Initial, Subsequent, Sequela
  • Ainitial encounter this code
  • Dsubsequent encounter
  • Ssequela

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name T69.021A, its category, or a range that includes it.

Excludes2 2

These codes carry an Excludes2 note naming T69.021A: its condition is not part of those codes, and both may be reported when the patient has both.

  • I73 Other peripheral vascular diseases
    immersion hand or foot (T69.0-) names T69.0-, which includes this code
  • Block T33-T34 Frostbite
    hypothermia and other effects of reduced temperature (T68, T69.-) names T69.-, which includes this code

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INJ021
Effect of other external causes, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Immersion Foot

    a condition of the feet produced by prolonged exposure of the feet to water. exposure for 48 hours or more to warm water causes tropical immersion foot or warm-water immersion foot common in vietnam where troops were exposed to prolonged or repeated wading in paddy fields or streams. trench foot results from prolonged exposure to cold, without actual freezing. it was common in trench warfare during world war i, when soldiers stood, sometimes for hours, in trenches with a few inches of cold water in them. (andrews' diseases of the skin, 8th ed, p27)

Patient EducationClinical

Hypothermia

Cold weather can affect your body in different ways. You can get frostbite, which is an injury to the body that is caused by freezing. Your body can also lose heat faster than you can produce it. That can cause hypothermia, or abnormally low body temperature. It can make you sleepy, confused, and clumsy.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert T69.021A to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
991.4 Immersion foot
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About T69.021AOverview

What is the ICD-10 code for immersion foot, right foot, initial encounter?

The ICD-10-CM code for immersion foot, right foot, initial encounter is T69.021A (sometimes written as T69021A). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is T69.021A (Immersion foot, right foot) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report immersion foot, right foot, initial encounter on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What does the 7th character A in T69.021A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for immersion foot, right foot, such as an emergency visit or first evaluation.

What MS-DRG does T69.021A group to?

When immersion foot, right foot, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 923, 922, with relative weights from 0.9980 to 1.6248 depending on complications. Higher weights mean higher Medicare reimbursement.

Is T69.021A a CC or MCC?

CMS lists T69.021A as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 29 closely related codes in its exclusion list.