2027 ICD-10-CM Diagnosis Code Q40.1Congenital hiatus hernia

ICD-10-CM Codes›Q00-Q99›Q38-Q45›Q40

ICD-10-CM Q40.1
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

Q40.1 is a billable ICD-10-CM diagnosis code for congenital hiatus hernia. 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. The code is exempt from POA reporting. Coders also document this condition as congenital diaphragmatic hernia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Digestive congenital anomalies.

Code Identity

ICD-10-CM Code
Q40.1
Billable Status
Yes — Valid for Submission
Code Describes
Congenital hiatus hernia
Short Description
Congenital hiatus hernia
Same as the full description in the CMS dataset.
Parent Code
Q40
Other congenital malformations of upper alimentary tract

Code Classification

ChapterQ00-Q99Congenital malformations, deformations and chromosomal abnormalities
SectionQ38-Q45Other congenital malformations of the digestive system
CategoryQ40Other congenital malformations of upper alimentary tract
This CodeQ40.1Congenital hiatus hernia

Present on Admission (POA)Billing

Q40.1 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review the other POA exempt codes in Other congenital malformations of the digestive system (Q38-Q45).

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Congenital diaphragmatic hernia
  • Congenital hiatus hernia
  • Galloway Mowat syndrome
  • Steroid-resistant nephrotic syndrome

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to Q40.1: its own notes plus those printed at Chapter 17. 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.

  • Congenital displacement of cardia through esophageal hiatus

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

  • congenital diaphragmatic hernia (Q79.0)

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.

From Chapter 17 (Q00-QA1) Congenital malformations, deformations and chromosomal abnormalities applies to 900 codes
  • inborn errors of metabolism (E70-E88)

Notes

General instructions on how these codes are used.

From Chapter 17 (Q00-QA1) Congenital malformations, deformations and chromosomal abnormalities applies to 900 codes
  • Codes from this chapter are not for use on maternal records

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name Q40.1, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming Q40.1: they are not reported together with it, unless the two conditions are unrelated.

  • K44 Diaphragmatic hernia
    congenital hiatus hernia (Q40.1)
  • Q79.0 Congenital diaphragmatic hernia
    congenital hiatus hernia (Q40.1)

Excludes2 1

These codes carry an Excludes2 note naming Q40.1: its condition is not part of those codes, and both may be reported when the patient has both.

  • Q45 Other congenital malformations of digestive system
    congenital hiatus hernia (Q40.1)

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.

CCSR MAL002
Digestive congenital anomalies
Default principal diagnosis: inpatient Yes · outpatient Yes

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

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert Q40.1 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
750.6 Congenital hiatus hernia
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About Q40.1Overview

What is the ICD-10 code for congenital hiatus hernia?

The ICD-10-CM code for congenital hiatus hernia is Q40.1 (sometimes written as Q401). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is Q40.1 (Other congenital malformations of upper alimentary tract) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report congenital hiatus hernia on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does Q40.1 group to?

When congenital hiatus hernia is the principal diagnosis on an inpatient stay, it groups to MS-DRG 394, 395, 393, with relative weights from 0.6379 to 1.5877 depending on complications. Higher weights mean higher Medicare reimbursement.

Is Q40.1 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 hiatus hernia on inpatient claims. The code appears in the Other congenital malformations of the digestive system (Q38-Q45) range of the CMS exempt list.

Can Q40.1 be reported with Q79.0?

Not as a rule. The Excludes1 note on Q40.1 lists "congenital diaphragmatic hernia (Q79.0)". 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).