Skip to main content

S31.815 ICD-10-CM Code: Open bite of right buttock

Compare with another code for S31.815Check 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

7th character
Required — see the character table on this page
Tabular directives
7 inclusion terms · 2 Excludes1 · 8 Excludes2 · 3 code-also instructions

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, and is marked with where it comes from.

7th character:required: report a code with a 7th character· The appropriate 7th character is to be added to each code from category S31See the 7th character note

Excludes1Not reported with this code unless documented as unrelated
  • superficial bite of buttock (S30.870)
  • traumatic amputation of part of abdomen, lower back and pelvis (S38.2-, S38.3) (from S31)
Code alsofrom S31May be needed with this code
Excludes2Not included here; may be reported together
  • open wound of hip (S71.00-S71.02) (from S31)
  • open fracture of pelvis (S32.1--S32.9 with 7th character B) (from S31)
  • burns and corrosions (T20-T32) (from S30-S39)
  • effects of foreign body in anus and rectum (T18.5) (from S30-S39)

+4 more in Instructions

IncludesWhat this code covers
  • injuries to the abdominal wall (from S30-S39)
  • injuries to the anus (from S30-S39)
  • injuries to the buttock (from S30-S39)
  • injuries to the external genitalia (from S30-S39)

+3 more in Instructions

Where it sits Source: CMS/NCHS

Under:Chapter 19: Injury, Poisoning and Certain Other Consequences of External CausesS30-S39 Injuries to the abdomen, lower back, lumbar spine, pelvis and external genitalsS31 Open wound of abdomen, lower back, pelvis and external genitalsS31.8 Open wound of other parts of abdomen, lower back and pelvisS31.81 Open wound of right buttock

Codes under S31.815 (3)

  • S31.815AOpen bite of right buttock, initial encounterBillable
  • S31.815DOpen bite of right buttock, subsequent encounterBillable
  • S31.815SOpen bite of right buttock, sequelaBillable

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 S31.815 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 S31.815 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.

  • injuries to the abdominal wall
  • injuries to the anus
  • injuries to the buttock
  • injuries to the external genitalia
  • injuries to the flank
  • injuries to the groin

Source: inherited from S30-S39

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Bite of right buttock NOS

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).

Excludes2 — Not Included Here

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

Code Also

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

Source: inherited from S31

7th Character Guide

"The appropriate 7th character is to be added to each code from category S31"

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

How the encounter character is assigned. “Initial encounter” means the patient is receiving active treatment for the condition — it is not limited to the first visit, and a different or new provider giving active treatment still assigns it. “Subsequent encounter” covers care during the healing or recovery phase after active treatment. “Sequela” is for complications or conditions that arise as a direct result of the original condition.

ICD-10-CM Official Guidelines for Coding and Reporting, Section I.C.19.a (paraphrased by MedCoder).

Variant codes in this family

S31.815A, S31.815D, S31.815S

Character meanings are CMS's official 7th-character extensions for this family, as carried in each variant code's official description; variant codes are registry rows. The explanation of how the encounter character is assigned is MedCoder editorial, distinct from the official content above it.

Coder workflow for S31.815

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

Before you code S31.815

  1. S31.815 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).

    ReviewS31.815A, S31.815D, S31.815S

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

  2. A 7th character is required in this family. Confirm the documented encounter: initial (active treatment), subsequent (healing or recovery phase), or sequela. S31.815 is not valid without one. “Initial” means active treatment, not the first visit (Guidelines I.C.19.a).

    See the 7th Character Guide · Guide: 7th characters: initial, subsequent, sequela →

  3. Laterality is coded in this family. Confirm the side documented — right, left, or bilateral — and select the matching code (this page’s code: right). The unspecified-side code applies only when the record states no side. Laterality is assigned from the documented side; where a bilateral code exists and both sides are documented, it is used instead of two unilateral codes (Guidelines I.B.13).

    See the relationships section · Guide: Laterality coding →

  4. Confirm the injury type, the anatomical site at the most specific level documented, laterality where the family codes it, and the encounter for the 7th character. Each injury is coded separately unless the classification provides a combination code, and a superficial injury is not coded when a more severe injury of the same site is documented. Injury chapter guidelines (Guidelines I.C.19.b, I.C.19.b.1).

    Guide: 7th characters: initial, subsequent, sequela →

  5. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with the code beneath S31.815. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the documentation support one of the more specific codes beneath S31.815?
    Yes → Select that code and continue the checks below on its own page.
    No → S31.815 cannot be reported as written. Where the codes beneath it include an unspecified code, that code applies when the record goes no further; otherwise query for the missing detail.

    ReviewS31.815A, S31.815D, S31.815S

  2. Does the documentation support a condition named in S31.815’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.

    ReviewS30.870, S38.2, S38.3

  3. Is the side documented?
    Yes → Select the code for the documented side (or the bilateral code when both sides are documented and one exists).
    No → Use the unspecified-side code only when the record states no side; a query is the alternative.
  4. Is the encounter phase documented — active treatment, healing or recovery, or a sequela?
    Yes → Assign the matching 7th character; the variant codes are in the 7th Character Guide.
    No → The code is invalid without its 7th character — query for the missing element.

Report the code beneath S31.815 that the documentation supports, not S31.815 itself. Then review the Code Also note, and confirm that code is valid for the date of service on its own page.

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).
Anatomical site
At the most specific level the record states; a site the classification separates cannot be assumed from a procedure or a measurement.
Laterality
Right, left or bilateral as documented; unspecified only when the record states no side (Guidelines I.B.13).
Encounter type
Active treatment, healing or recovery phase, or sequela — the basis of the 7th character (Guidelines I.C.19.a).
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).
Open or closed; displaced or nondisplaced
Defaults apply when the record is silent: closed, and displaced (Guidelines I.C.19.c).
External cause, place and activity
For the external cause codes reported with the injury or poisoning, where documented (Guidelines I.C.20.a).

Official instructions as workflow

  • Excludes1 — check before selecting S31.815(2 notes)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with S31.815: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareS30.870, S38.2, S38.3

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

  • Excludes2 — not part of S31.815(8 notes)

    Coding workflow: The conditions named in this note are not included in S31.815. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

    CompareS32.1, S32.9, T18.5, T19, T63.4

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

  • Code Also — related condition(3 notes)

    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.

    ReviewS24.0, S24.1, S34.0, S34.1

    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: Both the condition S31.815 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).

ReviewS30.870, S38.2, S38.3

Documentation: The patient returns during the healing or recovery phase after active treatment of the same condition.

Coding question: Which 7th character applies?

Path: Review the official 7th-character definitions for this family in the 7th Character Guide.

Reason: “Initial encounter” means active treatment, not the first visit; care during recovery takes “subsequent encounter”, and a complication arising from the original condition takes “sequela” (Guidelines I.C.19.a).

Documentation: The record documents the condition on one side only.

Coding question: Which code in this family applies?

Path: Select the sibling code for the documented side.

Reason: Laterality is assigned from the documented side; the unspecified-side code is for records that state no side (Guidelines I.B.13).

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 S31.815 with…

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

The codes most likely to be picked instead of S31.815 — 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.

  • S30.870— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of superficial bite of buttock moves the case to S30.870; the two are not reported together unless documented as unrelated.

    Full comparison: S31.815 vs S30.870 →

  • S38.2— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of traumatic amputation of part of abdomen, lower back and pelvis moves the case to S38.2; the two are not reported together unless documented as unrelated.

    Full comparison: S31.815 vs S38.2 →

  • S38.3— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of traumatic amputation of part of abdomen, lower back and pelvis moves the case to S38.3; the two are not reported together unless documented as unrelated.

    Full comparison: S31.815 vs S38.3 →

  • S31.819— Specificity relationship (Review)

    Overlapping diagnoses in the same category.

    Overlapping codes in the same category — the documentation decides which is the more specific fit.

    What moves you there: A record that documents no more than “Unspecified open wound of right buttock” takes S31.819; specificity in the record moves it back here.

    Full comparison: S31.815 vs S31.819 →

  • S31.815A— Encounter relationship (Review)

    Same underlying diagnosis, different encounter phase.

    The same diagnosis at a different phase of care; one encounter takes one 7th character.

    What moves you there: Documentation of a initial encounter moves the case to S31.815A.

    Full comparison: S31.815 vs S31.815A →

  • S31.815D— Encounter relationship (Review)

    Same underlying diagnosis, different encounter phase.

    The same diagnosis at a different phase of care; one encounter takes one 7th character.

    What moves you there: Documentation of a subsequent encounter moves the case to S31.815D.

    Full comparison: S31.815 vs S31.815D →

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

Open bite of right buttock is a non-billable ICD-10-CM category code (S31.815). 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.

Decision Points

The directives on this code's own record, as a pre-claim checklist.

  1. A 7th character applies in this family. Confirm the documented encounter matches the character assigned. See the official 7th-character definitions and this code’s variants
  2. Laterality is coded in this family. Confirm the documented side matches the code — the opposite-side siblings are in the relationships section. See the opposite-side sibling codes
  3. 3 Code Also notes — a second code may apply; the guidelines leave its sequencing to the circumstances of the encounter. See the Code Also notes
  4. 2 Excludes1 entries — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
  5. 8 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-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name S31.815 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 1 Use Additional Code instruction: S38.1 — Crushing injury of abdomen, lower back, and pelvis (via S31.-).

These codes instruct coders to additionally report this code when it applies.

Referenced by 5 Code Also instructions: S34 — Injury of lumbar and sacral spinal cord and nerves at abdomen, lower back and pelvis level (via S31.-), S35 — Injury of blood vessels at abdomen, lower back and pelvis level (via S31.-), S36 — Injury of intra-abdominal organs (via S31.-), S37 — Injury of urinary and pelvic organs (via S31.-), S39 — Other and unspecified injuries of abdomen, lower back, pelvis and external genitals (via S31.-).

These codes suggest coding this condition alongside when both are present.

Related Codes

Same condition, different side

Same title, differing only in which side of the body it names: right, left, bilateral or unspecified.

S31.805 — Open bite of unspecified buttock (unspecified)Compare S31.815 vs S31.805 →, S31.825 — Open bite of left buttock (left)Compare S31.815 vs S31.825 →

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Bite”; these codes share that main term but sit in a different category of the Tabular List.

S30.86A — Insect bite (nonvenomous) of flank (flank, superficial, insect), S30.870 — Other superficial bite of lower back and pelvis (pelvis, superficial NEC), S30.871 — Other superficial bite of abdominal wall (abdomen, abdominal, wall, superficial NEC), S30.872 — Other superficial bite of penis (penis, superficial NEC), S30.873 — Other superficial bite of scrotum and testes (testis, superficial NEC), S30.874 — Other superficial bite of vagina and vulva (vulva, superficial NEC), S30.875 — Other superficial bite of unspecified external genital organs, male (genital organs, external, male, superficial NEC), S30.876 — Other superficial bite of unspecified external genital organs, female (genital organs, external, female, superficial NEC), S30.877 — Other superficial bite of anus (anus, superficial NEC), S30.87A — Other superficial bite of flank (flank, superficial), S40.26 — Insect bite (nonvenomous) of shoulder (shoulder, superficial NEC, insect), S40.27 — Other superficial bite of shoulder (shoulder, superficial NEC), S40.86 — Insect bite (nonvenomous) of upper arm (arm, superficial NEC, insect), S40.87 — Other superficial bite of upper arm (arm, superficial NEC), S41.05 — Open bite of shoulder (shoulder), S41.15 — Open bite of upper arm (arm), S50.36 — Insect bite (nonvenomous) of elbow (elbow, superficial NEC, insect), S50.37 — Other superficial bite of elbow (elbow, superficial NEC), S50.86 — Insect bite (nonvenomous) of forearm (forearm, superficial NEC, insect), S50.87 — Other superficial bite of forearm (forearm, superficial NEC), +110 more

Contextual Map

Every relationship of S31.815 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 S31.815 with these 7 related codes in Claim Check

Hierarchy

Excludes1

Referenced by Use Additional Code instructions

Referenced by Code Also instructions

Index entries

  • Bite (s) (animal) (human), buttock, right[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027

Nearest codes (40)

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

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.

Indexed Clinical Terms (1)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

Common coding questions

MedCoder editorial

Can S31.815 be billed directly?

No. S31.815 (Open bite of right buttock) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.

Does S31.815 require a 7th character?

Yes. The appropriate 7th character is to be added to each code from category S31.

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. "S31.815 — Open bite of right buttock." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/s31.815-open-bite-of-right-buttock

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Open bite of right buttock

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027, 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 S31.815 in its code family, with their registry titles.

View all codes in the S31 family