B18 ICD-10-CM Code: Chronic viral hepatitis
Billing Status: NO. This is a clinician non-billable / parent hierarchy grouping in the ICD-10-CM system.
Coding at a Glance
- Tabular directives
- 1 inclusion term · 1 Excludes1 · 2 Excludes2 · 1 use-additional code
Coding instructions
Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for B18 in the official ICD-10-CM tabular list, quoted as published.
Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025
Notes without a marker are published on B18 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.
- Carrier of viral hepatitis
Excludes1 — Not Coded Here
Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
- sequelae of viral hepatitis (B94.2) Compare B18 vs B94.2 →
Source: inherited from B15-B19
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- cytomegaloviral hepatitis (B25.1) Compare B18 vs B25.1 →
- herpesviral [herpes simplex] hepatitis (B00.81) Compare B18 vs B00.81 →
Source: inherited from B15-B19
Use Additional Code
Supplementary codes the tabular list directs you to add.
- Use additional code, if applicable, for ascites (R18.8)
Coder workflow for B18
MedCoder structured workflow — derived from this code’s own official record
Before you code B18
- B18 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).
ReviewB18.0, B18.1, B18.2, B18.8, B18.9
See the relationships section · Guide: How to choose an ICD-10-CM code →
- Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with B18. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).
Choose the right path
- Does the documentation support one of the more specific codes beneath B18?
Yes → Select that code and continue the checks below on its own page.
No → B18 cannot be reported as written; query for the specificity its subcategory needs. - Does the documentation support a condition named in B18’s Excludes1 note?
Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
No → Continue.ReviewB94.2
Consider B18. Then work the Use Additional Code 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).
- Acuity
- Acute or chronic as documented; when both are documented and separate codes exist, both are reported with the acute code first (Guidelines I.B.8).
- The conditions the Use Additional Code note names
- Reported with this code when documented; a conditional instruction (“if applicable”, “if known”) applies only when the record supports it.
Official instructions as workflow
Excludes1 — check before selecting B18(1 note)
Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with B18: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.
CompareB94.2
See the official tabular notes · Guidelines I.A.12.a
Excludes2 — not part of B18(2 notes)
Coding workflow: The conditions named in this note are not included in B18. When the record documents both, both may be reported; the note is a boundary, not a prohibition.
See the official tabular notes · Guidelines I.A.12.b
Use Additional Code — after identifying B18(1 note)
Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with B18 when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.
ReviewR18.8
See the official tabular notes · Guidelines I.A.13
Coding decision scenarios
Pattern scenarios for this code’s structure — decision rules, not clinical cases
Documentation: Both the condition B18 describes and a condition named in its Excludes1 note are documented for the same encounter.
Coding question: Can both codes be reported?
Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.
Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).
ReviewB94.2
Documentation: A condition the Use Additional Code note names is documented.
Coding question: Is a second code reported with B18?
Path: Review the Use Additional Code note and the code it names.
Reason: The additional code is reported when the record documents the condition; a conditional instruction applies only when its condition is met (Guidelines I.A.13).
ReviewR18.8
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.
Code Overview
MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.
Decision Points
The directives on this code's own record, as a pre-claim checklist.
- 1 Use Additional Code instruction — report the named additional code(s) when the documentation supports them. See the Use Additional Code notes
- 1 Excludes1 entry — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
- 2 Excludes2 entries — those conditions are not part of this code and may be reported additionally when documented. See the Excludes2 notes
Checklist rows are derived from this code's own official directives; the wording of each check is MedCoder editorial. The official notes themselves are in the sections each row links to.
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 structured relationships — computed from published CMS and AHRQ datasets
Other codes that name B18 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 4 Excludes1 notes: K73 — Chronic hepatitis, not elsewhere classified, K75.2 — Nonspecific reactive hepatitis, K75.3 — Granulomatous hepatitis, not elsewhere classified, K75.9 — Inflammatory liver disease, unspecified.
These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.
Referenced by 11 Excludes2 notes across 3 chapters: K70 — Alcoholic liver disease, K70-K77 — Diseases of liver (K70-K77), K71 — Toxic liver disease, K72 — Hepatic failure, not elsewhere classified, K73 — Chronic hepatitis, not elsewhere classified, K74 — Fibrosis and cirrhosis of liver, K75 — Other inflammatory liver diseases, K76 — Other diseases of liver, K77 — Liver disorders in diseases classified elsewhere, T80.6 — Other serum reactions, Z22 — Carrier of infectious disease.
These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.
Referenced by 2 Code First instructions across 2 chapters: H67 — Otitis media in diseases classified elsewhere, M02 — Postinfective and reactive arthropathies.
Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.
Referenced by 1 Code Also instruction: K74 — Fibrosis and cirrhosis of liver.
These codes suggest coding this condition alongside when both are present.
Contextual Map
Every relationship of B18 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 B18 with these 17 related codes in Claim Check
Hierarchy
- A00-B99 — Chapter 1: Certain Infectious and Parasitic Diseases (A00-B99) (A00-B99)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B15-B19 — Viral hepatitis[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
Excludes1
- B94.2 — Sequelae of viral hepatitis[Excludes1]: “sequelae of viral hepatitis (B94.2)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Excludes2
- B00.81 — Herpesviral hepatitis[Excludes2]: “herpesviral [herpes simplex] hepatitis (B00.81)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- B25.1 — Cytomegaloviral hepatitis[Excludes2]: “cytomegaloviral hepatitis (B25.1)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Use Additional Code
- R18.8 — Other ascites[Use Additional Code]: “code, if applicable, for ascites (R18.8)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Referenced by Excludes1 notes
- K73 — Chronic hepatitis, not elsewhere classified[Excludes1]: “viral hepatitis (chronic) (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K75.2 — Nonspecific reactive hepatitis[Excludes1]: “viral hepatitis (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K75.3 — Granulomatous hepatitis, not elsewhere classified[Excludes1]: “viral hepatitis (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K75.9 — Inflammatory liver disease, unspecified[Excludes1]: “viral hepatitis (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Referenced by Excludes2 notes (11)
- K70 — Alcoholic liver disease[Excludes2]: “viral hepatitis (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K70-K77 — Diseases of liver (K70-K77)[Excludes2]: “viral hepatitis (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K71 — Toxic liver disease[Excludes2]: “viral hepatitis (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K72 — Hepatic failure, not elsewhere classified[Excludes2]: “viral hepatitis with hepatic coma (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K73 — Chronic hepatitis, not elsewhere classified[Excludes2]: “viral hepatitis (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K74 — Fibrosis and cirrhosis of liver[Excludes2]: “viral hepatitis (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K75 — Other inflammatory liver diseases[Excludes2]: “viral hepatitis (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K76 — Other diseases of liver[Excludes2]: “viral hepatitis (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- and 3 more
Referenced by Code First instructions
- H67 — Otitis media in diseases classified elsewhere[Code First]: “viral disease NEC (B00-B34)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- M02 — Postinfective and reactive arthropathies[Code First]: “viral hepatitis (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Referenced by Code Also instructions
- K74 — Fibrosis and cirrhosis of liver[Code Also]: “, if applicable, viral hepatitis (acute) (chronic) (B15-B19)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Nearest codes
- B18.0 — Chronic viral hepatitis B with delta-agent[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B18.1 — Chronic viral hepatitis B without delta-agent[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B18.2 — Chronic viral hepatitis C[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B18.8 — Other chronic viral hepatitis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B18.9 — Chronic viral hepatitis, unspecified[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
Change history
- FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016
Common coding questions
Can B18 be billed directly?
No. B18 (Chronic viral hepatitis) 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 FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
- Claim edits Official source data
- CMS Definitions of Medicare Code Edits — v43.1 (April 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 structured 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 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.
Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates
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. "B18 — Chronic viral hepatitis." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/b18-chronic-viral-hepatitis
Change history
- FY2016 — October 1, 2015In the code set at ICD-10-CM adoptionChronic viral hepatitis
No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.
Nearest Codes in This Family
Official ICD-10-CM classifications closest to B18 in its code family, with their registry titles.