FY2027 ICD-10-CM reference
K55.30: Necrotizing enterocolitis, unspecified
By the HCC Buddy Coding Team
The official ICD-10-CM descriptor is Necrotizing enterocolitis, unspecified. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Billable code. Verified against the official FY2027 order file.
FY2027 Tabular instructions
Instructions below include applicable chapter, section and parent-code notes. Each note identifies where it appears in the official source.
Excludes2
certain conditions originating in the perinatal period (P04-P96)
Source: K00-K95 (chapter, inherited).
Excludes2
certain infectious and parasitic diseases (A00-B99)
Source: K00-K95 (chapter, inherited).
Excludes2
complications of pregnancy, childbirth and the puerperium (O00-O9A)
Source: K00-K95 (chapter, inherited).
Excludes2
congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
Source: K00-K95 (chapter, inherited).
Excludes2
endocrine, nutritional and metabolic diseases (E00-E88)
Source: K00-K95 (chapter, inherited).
Excludes2
injury, poisoning and certain other consequences of external causes (S00-T88)
Source: K00-K95 (chapter, inherited).
Excludes2
neoplasms (C00-D49)
Source: K00-K95 (chapter, inherited).
Excludes2
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Source: K00-K95 (chapter, inherited).
Excludes1
necrotizing enterocolitis of newborn (P77.-)
Source: K55 (category, inherited).
Excludes2
angioectasia (angiodysplasia) duodenum (K31.81-)
Source: K55 (category, inherited).
Excludes1
necrotizing enterocolitis of newborn (P77.-)
Source: K55.3 (self, inherited).
Excludes2
necrotizing enterocolitis due to Clostridium difficile (A04.7-)
Source: K55.3 (self, inherited).
Instructional note
Necrotizing enterocolitis, NOS
Source: K55.30 (self, direct).
Compare the FY2027 additions, removals and billable-status changes
What does K55.30 mean in FY2027?
The official ICD-10-CM descriptor is Necrotizing enterocolitis, unspecified. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Is K55.30 billable in FY2027?
The FY2027 order file marks K55.30 as billable. Check the complete Tabular instructions and documentation before assigning it.
Does K55.30 map to an HCC?
K55.30 has no CMS-HCC V28 category in the CMS 2027 Initial ICD-10-CM Mappings (payment year 2027, 2026 dates of service). Under the PY2026 CMS mapping; CMS 2027 initial file unchanged: ESRD HCC 107 (CMS lists the same category for every age band in its model mapping); no RxHCC category. Coefficients for these models are pending verification for payment year 2027. HHS-HCC: HCC 42 and HCC 154 (HCC 42: This code has a CMS age requirement: applies when age < 2; HCC 154: This code has a CMS age requirement: applies when age >= 2) under the HHS-HCC 2026 benefit year mapping (no RAF; HHS-HCC weights vary by metal level). CMS-HCC V24: not used for payment year 2027 Medicare Advantage payment (CMS CY 2027 Rate Announcement). The PACE mapping is still pending verification for FY2027.
Source: CMS FY2027 ICD-10-CM order file. Payment model: CMS CY 2027 Rate Announcement. Read the FY2027 Official Guidelines.
Review the FY2026 April edition