FY2027 ICD-10-CM reference
M35: Other systemic involvement of connective tissue
By the HCC Buddy Coding Team
The official ICD-10-CM descriptor is Other systemic involvement of connective tissue. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Nonbillable heading. Verified against the official FY2027 order file.
Oct to Dec 2026, PY2027
CMS-HCC V28
Not applicableCMS-HCC V24
Not applicableESRD
Not applicableRxHCC
Not applicablePACE (CMS-HCC V22 component)
Not applicablePACE ESRD (ESRD V21 component)
Not applicablePACE RxHCC (2018/2019 component)
Not applicableJan to Sep 2027, PY2028
CMS-HCC V28
Not applicableCMS-HCC V24
Not applicableESRD
Not applicableRxHCC
Not applicablePACE (CMS-HCC V22 component)
Not applicablePACE ESRD (ESRD V21 component)
Not applicablePACE RxHCC component
Not applicableOct to Dec 2026, BY2026
HHS-HCC
Not applicableJan to Sep 2027, BY2027
HHS-HCC
Not applicableMore specific FY2027 codes
- M35.0: Sjögren syndromeNonbillable heading
- M35.1: Other overlap syndromesBillable code
- M35.2: Behçet's diseaseBillable code
- M35.3: Polymyalgia rheumaticaBillable code
- M35.4: Diffuse (eosinophilic) fasciitisBillable code
- M35.5: Multifocal fibrosclerosisBillable code
- M35.6: Relapsing panniculitis [Weber-Christian]Billable code
- M35.7: Hypermobility syndromeBillable code
- M35.8: Other specified systemic involvement of connective tissueNonbillable heading
- M35.9: Systemic involvement of connective tissue, unspecifiedBillable code
FY2027 Tabular instructions
Instructions below include applicable chapter, section and parent-code notes. Each note identifies where it appears in the official source.
Instructional note
Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition
Source: M00-M99 (chapter, inherited).
Excludes2
arthropathic psoriasis (L40.5-)
Source: M00-M99 (chapter, inherited).
Excludes2
certain conditions originating in the perinatal period (P04-P96)
Source: M00-M99 (chapter, inherited).
Excludes2
certain infectious and parasitic diseases (A00-B99)
Source: M00-M99 (chapter, inherited).
Excludes2
compartment syndrome (traumatic) (T79.A-)
Source: M00-M99 (chapter, inherited).
Excludes2
complications of pregnancy, childbirth and the puerperium (O00-O9A)
Source: M00-M99 (chapter, inherited).
Excludes2
congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
Source: M00-M99 (chapter, inherited).
Excludes2
endocrine, nutritional and metabolic diseases (E00-E88)
Source: M00-M99 (chapter, inherited).
Excludes2
injury, poisoning and certain other consequences of external causes (S00-T88)
Source: M00-M99 (chapter, inherited).
Excludes2
neoplasms (C00-D49)
Source: M00-M99 (chapter, inherited).
Excludes2
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Source: M00-M99 (chapter, inherited).
Includes
autoimmune disease NOS
Source: M30-M36 (section, inherited).
Includes
collagen (vascular) disease NOS
Source: M30-M36 (section, inherited).
Includes
systemic autoimmune disease
Source: M30-M36 (section, inherited).
Includes
systemic collagen (vascular) disease
Source: M30-M36 (section, inherited).
Excludes1
autoimmune disease, single organ or single cell-type -code to relevant condition category
Source: M30-M36 (section, inherited).
Excludes1
reactive perforating collagenosis (L87.1)
Source: M35 (category, direct).
Compare the FY2027 additions, removals and billable-status changes
What does M35 mean in FY2027?
The official ICD-10-CM descriptor is Other systemic involvement of connective tissue. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Is M35 billable in FY2027?
The FY2027 order file marks M35 as a nonbillable heading. Select a complete billable child code.
Does M35 map to an HCC?
Risk-model mapping is not applicable to this nonbillable heading. Check a complete billable child code.
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