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Z77.3 ICD-10-CM Code: Contact with and (suspected) exposure to war theater

Compare with another codeCheck this code on a claim

Billing Status: NO. This is a non-billable ICD-10-CM code: report a more specific billable code beneath it.

Coding at a Glance

Tabular directives
1 inclusion term · 7 Excludes2 · 1 code-also instruction

Not billable · FY2027A non-billable heading in the tabular list: report a more specific code beneath it.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too; the Instructions section marks which is which.

Code alsoMay be needed with this code
  • any follow-up examination (Z08-Z09)
Excludes2Not included here; may be reported together
  • contact with and (suspected) exposure to communicable diseases (Z20.-)
  • exposure to (parental) (environmental) tobacco smoke in the perinatal period (P96.81)
  • newborn affected by noxious substances transmitted via placenta or breast milk (P04.-)
  • occupational exposure to risk factors (Z57.-)

+3 more in Instructions

IncludesWhat this code covers
  • contact with and (suspected) exposures to potential hazards to health

Most relevant related codes MedCoder-derived

Read off the official notes above and this code’s own position in the tabular list. Which to report is a documentation question; Compare shows the two side by side.

CompareCheck ClaimView Related Codes

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for Z77.3 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on Z77.3 itself; “inherited from” names the category or block whose note applies here.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

  • contact with and (suspected) exposures to potential hazards to health

Source: inherited from Z77

Excludes2 — Not Included Here

Conditions not covered by this code, but which may be reported alongside it when both are present.

Source: inherited from Z77

Code Also

Additional codes that may be required to fully describe the encounter.

  • any follow-up examination (Z08-Z09)

Source: inherited from Z77-Z99

Coder workflow for Z77.3

MedCoder structured workflow — derived from this code’s own official record

Before you code Z77.3

  1. Z77.3 is not reportable as written. Select the more specific code beneath it that the documentation supports. Codes are reported to the highest level of specificity the classification provides (Guidelines I.B.2).

    ReviewZ77.31, Z77.32, Z77.33, Z77.39

    See the relationships section · Guide: How to choose an ICD-10-CM code →

  2. Z77.3’s title joins a condition with an associated condition or complication. Confirm each component is documented. Where the classification presumes the link through the “with” convention, only a provider statement that the conditions are unrelated defeats it. A combination code is assigned only when it fully identifies the documented conditions; a required second code for the stage, type or manifestation is still reported when the notes ask for it (Guidelines I.B.9, I.A.15).

    Guide: Combination codes →

  3. Confirm the reason for the encounter this Z code records: the circumstance it records. Check whether the code may be reported as first-listed or principal — some Z codes are limited to one position — and do not report a history or status code for a condition documented as current. Z code categories and their reporting positions (Guidelines I.C.21.c, I.C.21.c.15).

    Guide: Z codes as principal or first-listed diagnosis →

Choose the right path

  1. Does the documentation support one of the more specific codes beneath Z77.3?
    Yes → Select that code and continue the checks below on its own page.
    No → Z77.3 cannot be reported as written; query for the specificity its subcategory needs.

    ReviewZ77.31, Z77.32, Z77.33, Z77.39

Consider Z77.3. Then review the Code Also note, and confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
The associated condition or complication
Whether the associated condition the title names is documented; the “with” convention presumes some links, and a provider statement that the conditions are unrelated defeats it (Guidelines I.A.15).
The reason for the encounter
Whether the code records the encounter’s purpose, a status, or a history — and whether it may be first-listed (Guidelines I.C.21.c).

Official instructions as workflow

  • Excludes2 — not part of Z77.3(7 notes)

    Coding workflow: The conditions named in this note are not included in Z77.3. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

    CompareZ20, P96.81, P04, Z57, Z18, Z87.821

    See the official tabular notes · Guidelines I.A.12.b

  • Code Also — related condition(1 note)

    Coding workflow: Review the related condition when both are documented and the instruction applies. A Code Also note does not fix sequencing; the order follows the circumstances of the encounter.

    See the official tabular notes · Guidelines I.A.17

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: Only one of the components this code’s title joins is documented.

Coding question: Is Z77.3 supported?

Path: Review the code for the documented component on its own.

Reason: A combination code is assigned only when it fully identifies the documented conditions; otherwise the documented component takes its own code (Guidelines I.B.9).

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Don’t confuse Z77.3 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of Z77.3 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

  • Z20— Excludes2 relationship (Informational)

    Distinct conditions — both may be reported.

    A distinct condition — both may be reported when both are documented.

    What moves you there: Documentation of contact with and (suspected) exposure to communicable diseases adds Z20; it is not part of this code and both may be reported when both are documented.

    Full comparison: Z77.3 vs Z20 →

  • P96.81— Excludes2 relationship (Informational)

    Distinct conditions — both may be reported.

    A distinct condition — both may be reported when both are documented.

    What moves you there: Documentation of exposure to (parental) (environmental) tobacco smoke in the perinatal period adds P96.81; it is not part of this code and both may be reported when both are documented.

    Full comparison: Z77.3 vs P96.81 →

  • P04— Excludes2 relationship (Informational)

    Distinct conditions — both may be reported.

    A distinct condition — both may be reported when both are documented.

    What moves you there: Documentation of newborn affected by noxious substances transmitted via placenta or breast milk adds P04; it is not part of this code and both may be reported when both are documented.

    Full comparison: Z77.3 vs P04 →

  • Z57— Excludes2 relationship (Informational)

    Distinct conditions — both may be reported.

    A distinct condition — both may be reported when both are documented.

    What moves you there: Documentation of occupational exposure to risk factors adds Z57; it is not part of this code and both may be reported when both are documented.

    Full comparison: Z77.3 vs Z57 →

  • Z18— Excludes2 relationship (Informational)

    Distinct conditions — both may be reported.

    A distinct condition — both may be reported when both are documented.

    What moves you there: Documentation of retained foreign body adds Z18; it is not part of this code and both may be reported when both are documented.

    Full comparison: Z77.3 vs Z18 →

  • Z87.821— Excludes2 relationship (Informational)

    Distinct conditions — both may be reported.

    A distinct condition — both may be reported when both are documented.

    What moves you there: Documentation of retained foreign body fully removed adds Z87.821; it is not part of this code and both may be reported when both are documented.

    Full comparison: Z77.3 vs Z87.821 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Contact with and (suspected) exposure to war theater is a non-billable ICD-10-CM category code (Z77.3). A more specific billable subcode must be selected for claims submission.

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Verify Before Coding

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name Z77.3 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 18 Excludes1 notes across 2 chapters: T51 — Toxic effect of alcohol (via Z77.-), T51-T65 — Toxic effects of substances chiefly nonmedicinal as to source (T51-T65) (via Z77.-), T52 — Toxic effect of organic solvents (via Z77.-), T53 — Toxic effect of halogen derivatives of aliphatic and aromatic hydrocarbons (via Z77.-), T54 — Toxic effect of corrosive substances (via Z77.-), T55 — Toxic effect of soaps and detergents (via Z77.-), T56 — Toxic effect of metals (via Z77.-), T57 — Toxic effect of other inorganic substances (via Z77.-), T58 — Toxic effect of carbon monoxide (via Z77.-), T59 — Toxic effect of other gases, fumes and vapors (via Z77.-), T60 — Toxic effect of pesticides (via Z77.-), T61 — Toxic effect of noxious substances eaten as seafood (via Z77.-), T62 — Toxic effect of other noxious substances eaten as food (via Z77.-), T63 — Toxic effect of contact with venomous animals and plants (via Z77.-), T64 — Toxic effect of aflatoxin and other mycotoxin food contaminants (via Z77.-), T65 — Toxic effect of other and unspecified substances (via Z77.-), Z03 — Encounter for medical observation for suspected diseases and conditions ruled out (via Z77.-), Z13.88 — Encounter for screening for disorder due to exposure to contaminants (via Z77.-).

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 2 Excludes2 notes across 2 chapters: P04 — Newborn affected by noxious substances transmitted via placenta or breast milk (via Z77.-), Z91 — Personal risk factors, not elsewhere classified (via Z77.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

Contextual Map

Every relationship of Z77.3 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run Z77.3 with these 10 related codes in Claim Check

Hierarchy

Referenced by Excludes1 notes (18)

Referenced by Excludes2 notes

Nearest codes (40)

Change history

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Common coding questions

MedCoder editorial

Can Z77.3 be billed directly?

No. Z77.3 (Contact with and (suspected) exposure to war theater) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 2026) Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder-derived relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder editorial explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 28, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "Z77.3 — Contact with and (suspected) exposure to war theater." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/z77.3-contact-with-and-suspected-exposure-to-war-theater

Change history

  • FY2026 — October 1, 2025
    Added to the code set
    Contact with and (suspected) exposure to war theater
    FY2026 changes

Nearest Codes in This Family

Official ICD-10-CM classifications closest to Z77.3 in its code family, with their registry titles.

View all codes in the Z77 family