2026 ICD-10-CM Diagnosis Code Q31.9Congenital malformation of larynx, unspecified
ICD-10-CM Codes›Q00-Q99›Q30-Q34›Q31
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- POA Exempt
- Chronic Condition
Q31.9 is a billable ICD-10-CM diagnosis code for congenital malformation of larynx, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 11 through 13, 154 through 156. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 18 closely related codes. The code is exempt from POA reporting. Coders also document this condition as congenital anomaly of larynx. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Respiratory congenital malformations.
Code Identity
Code Classification
Present on Admission (POA)Billing
Q31.9 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review the other POA exempt codes in Congenital malformations of the respiratory system (Q30-Q34).
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Congenital anomaly of larynx
- Congenital malformation of larynx and trachea
- Short rib dysplasia
- Thoracolaryngopelvic dysplasia
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Birth Defects
A birth defect is a problem that happens while a baby is developing in the mother's body. Most birth defects happen during the first 3 months of pregnancy. One out of every 33 babies in the United States is born with a birth defect.
The full article covers:
- What are birth defects?
- What causes birth defects?
- Who is at risk of having a baby with birth defects?
- How are birth defects diagnosed?
- What are the treatments for birth defects?
- Can birth defects be prevented?
Read the full article at MedlinePlus
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Convert Q31.9 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About Q31.9Overview
What is the ICD-10 code for congenital malformation of larynx, unspecified?
The ICD-10-CM code for congenital malformation of larynx, unspecified is Q31.9 (sometimes written as Q319). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is Q31.9 (Congenital malformations of larynx) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report congenital malformation of larynx, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does Q31.9 group to?
When congenital malformation of larynx, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 11, 12, 13, 154, 155, 156, with relative weights from 0.6911 to 5.4541 depending on complications. Higher weights mean higher Medicare reimbursement.
Is Q31.9 a CC or MCC?
CMS lists Q31.9 as a CC (complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 18 closely related codes in its exclusion list.
Is Q31.9 exempt from POA reporting?
Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for congenital malformation of larynx, unspecified on inpatient claims. The code appears in the Congenital malformations of the respiratory system (Q30-Q34) range of the CMS exempt list.
