Is ICD-10-CM code K31.B billable?

Yes, K31.B (Hypertrophic pyloric stenosis, in childhood) is a billable ICD-10-CM diagnosis code, valid for reimbursement on HIPAA-covered transactions for FY2027.

What chapter does ICD-10-CM code K31.B belong to?

K31.B belongs to Chapter 11 of the ICD-10-CM tabular list: K00–K95 (Diseases of the Digestive System).

Is K31.B a new ICD-10-CM code for 2027?

Yes, K31.B was added or revised in the FY2027 ICD-10-CM update, effective October 1, 2026, as published by the Centers for Medicare and Medicaid Services (CMS).

K31.BBillableCCNew for FY2027Pediatric

Hypertrophic pyloric stenosis, in childhood

Diseases of the Digestive System·Other diseases of stomach and duodenum·subcategory·FY 2027

Stomach Disorders: Your stomach is an organ between your esophagus and small intestine. It is where digestion of protein begins. The stomach has three tasks. It stores swallowed food. It mixes the food with stomach acids. Then it sends the mixture on to the small intestine.

Read more about stomach disorders on MedlinePlus · Source: MedlinePlus, National Library of Medicine

Also indexed as: Stenosis, pylorus, in childhood; Stenosis, pylorus, infantile; Stenosis, pylorus, pediatric; Stricture, pylorus, infantile

Instructional notes

Includes: conditions that are coded here

Infantile hypertrophic pyloric stenosis
Pediatric hypertrophic pyloric stenosis
Pediatric pyloric stenosis

Excludes1: not coded here, use a different code

congenital pyloric stenosis (Q40.0)

Also applies, from K31: Other diseases of stomach and duodenum

These notes sit on K31 and apply to every code under it, including K31.B.

Includes: conditions that are coded here

functional disorders of stomach

Excludes2: not included here, code separately if applicable

diabetic gastroparesis (E08.43, E09.43, E10.43, E11.43, E13.43)
diverticulum of duodenum (K57.00-K57.13)

Also applies, from Diseases of esophagus, stomach and duodenum (K20-K31)

These notes sit on K20-K31 and apply to every code under it, including K31.B.

Excludes2: not included here, code separately if applicable

hiatus hernia (K44.-)

Where K31.B sits

K20-K31 Diseases of esophagus, stomach and duodenum (K20-K31)
K31 Other diseases of stomach and duodenum
K31.B Hypertrophic pyloric stenosis, in childhood

MS-DRGs

As the principal diagnosis, this code groups to these MS-DRGs (v44.0). Which one applies depends on procedures performed, secondary diagnoses (CC/MCC), and the patient's age and discharge status.

Code history

FY 2026: replaced Q40.0 (Congenital hypertrophic pyloric stenosis)