2027 ICD-10-CM Diagnosis Code K63.1Perforation of intestine (nontraumatic)
ICD-10-CM Codes›K00–K95›K55-K64›K63
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- Risk Adjusts — HCC 78
- Not Chronic
K63.1 is a billable ICD-10-CM diagnosis code for perforation of intestine (nontraumatic). It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 393 through 395, 791, 793. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 1 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Gastrointestinal and biliary perforation.
For Medicare Advantage risk adjustment, K63.1 maps to CMS-HCC Category 78 (Intestinal Obstruction/Perforation) under the V28 model, adding a risk factor of about 0.326 for a community, non-dual, aged beneficiary in payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
K63.1 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.
Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Delayed perforation of colon
- Delayed perforation of duodenum
- Delayed perforation of rectum
- Delayed perforation of small intestine
- Gastrointestinal perforation
- Inflammatory perforation of small intestine
- Injury of sigmoid colon
- Injury of transverse colon
- Neonatal obstruction of intestine
- Nontraumatic perforation of large intestine
- Nontraumatic perforation of small intestine
- Perforated ulcer of intestine
- Perforation of colon
- Perforation of ileum
- Perforation of intestine
- Perforation of intestine due to cystic fibrosis with meconium ileus
- Perforation of jejunum
- Perforation of large intestine
- Perforation of rectum
- Perforation of sigmoid colon
- Perforation of small intestine
- Perforation of terminal ileum
- Perforation of transverse colon
- Perinatal intestinal obstruction
- Perinatal intestinal perforation
- Rupture of colon
- Rupture of ileum
- Rupture of intestine
- Rupture of jejunum
- Rupture of rectum
- Rupture of small intestine
- Spontaneous perforation of large intestine
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to K63.1: its own notes plus those printed at Chapter 11. A note printed at a category, block or chapter applies to every code under it.
Applicable To
Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.
- Perforation (nontraumatic) of rectum
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name K63.1, its category, or a range that includes it.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Perforation, perforated (nontraumatic) (of)
bowel K63.1
colon K63.1
ileum K63.1
intestine NEC K63.1
ulcerative NEC K63.1
jejunum, jejunal K63.1
rectum K63.1
sigmoid K63.1
bowel (nontraumatic) K63.1
colon (nontraumatic) K63.1
rectum (nontraumatic) K63.1
sigmoid (nontraumatic) K63.1
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Intestinal Perforation
a rupture in the wall of the small or large intestine due to traumatic or pathologic processes.
Patient EducationClinical
Colonic Diseases
Your colon, also known as the large intestine, is part of your digestive system. It's a long, hollow tube at the end of your digestive tract where your body makes and stores stool. Many disorders affect the colon's ability to work properly. Some of these include:
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert K63.1 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About K63.1Overview
What is the ICD-10 code for perforation of intestine (nontraumatic)?
The ICD-10-CM code for perforation of intestine (nontraumatic) is K63.1 (sometimes written as K631). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is K63.1 (Other diseases of intestine) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report perforation of intestine (nontraumatic) on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does K63.1 group to?
When perforation of intestine (nontraumatic) is the principal diagnosis on an inpatient stay, it groups to MS-DRG 793, 791, 394, 395, 393, with relative weights from 0.6379 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.
Is K63.1 a CC or MCC?
CMS lists K63.1 as an MCC (major complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 1 closely related codes in its exclusion list.
Can K63.1 be reported with a code from K26?
Not as a rule. The Excludes1 note on K63.1 lists "perforation (nontraumatic) of duodenum (K26.-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).
What HCC is K63.1?
K63.1 (perforation of intestine (nontraumatic)) maps to CMS-HCC Category 78 (Intestinal Obstruction/Perforation), commonly written as HCC 78, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 33 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.
Does K63.1 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, K63.1 adds a risk adjustment factor of about 0.326 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.326 to 0.688 depending on the payment segment). A more severe related category (HCC 77) supersedes it when both are reported. See the full factor table on the HCC 78 category page.
