2026 ICD-10-CM Diagnosis Code Q66.6Other congenital valgus deformities of feet

ICD-10-CM Codes›Q00-Q99›Q65-Q79›Q66

ICD-10-CM Q66.6
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

Q66.6 is a billable ICD-10-CM diagnosis code for other congenital valgus deformities of feet. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 564 through 566. The code is exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Musculoskeletal congenital conditions.

Code Identity

ICD-10-CM Code
Q66.6
Billable Status
Yes — Valid for Submission
Code Describes
Other congenital valgus deformities of feet
Short Description
Other congenital valgus deformities of feet
Same as the full description in the CMS dataset.
Parent Code
Q66
Congenital deformities of feet

Code Classification

ChapterQ00-Q99Congenital malformations, deformations and chromosomal abnormalities
SectionQ65-Q79Congenital malformations and deformations of the musculoskeletal system
CategoryQ66Congenital deformities of feet
This CodeQ66.6Other congenital valgus deformities of feet

Present on Admission (POA)Billing

Q66.6 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Bilateral congenital hallux valgus
  • Bilateral congenital hallux valgus due to metatarsus primus varus
  • Bilateral congenital metatarsus valgus
  • Bilateral hallux valgus
  • Bilateral talipes valgus of feet
  • Congenital anomaly of macula
  • Congenital coloboma of macula lutea
  • Congenital forefoot valgus
  • Congenital hallux valgus
  • Congenital hallux valgus due to metatarsus primus varus
  • Congenital hallux valgus of left great toe
  • Congenital hallux valgus of right great toe
  • Congenital metatarsus valgus
  • Congenital rearfoot valgus
  • Congenital valgus deformity of foot
  • Hallux valgus due to metatarsus primus varus
  • Hallux valgus of left foot
  • Hallux valgus of right foot
  • Left congenital hallux valgus due to metatarsus primus varus
  • Macular coloboma, cleft palate, hallux valgus syndrome
  • Right congenital hallux valgus due to metatarsus primus varus
  • Severe intellectual disability, hypotonia, strabismus, coarse face, planovalgus syndrome
  • Talipes equinovalgus
  • Talipes equinus
  • Talipes planovalgus
  • Talipes valgus
  • Talipes valgus of left foot
  • Talipes valgus of right foot

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Congenital metatarsus valgus

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Deformity
      • foot (acquired)
        • valgus (congenital)
    • Eversion
      • foot NEC
        • congenital
    • Hallux
      • valgus (acquired)
        • congenital
    • Metatarsus, metatarsal
      • valgus (abductus), congenital
    • Pes(congenital)
      • valgus
    • Talipes(congenital)
      • equinovalgus
    • Talipes(congenital)
      • planovalgus
    • Talipes(congenital)
      • valgus

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR MAL008
Musculoskeletal congenital conditions
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Congenital Hallux Valgus

    hallux valgus that is present at birth.

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 Q66.6 to ICD-9-CMHistory

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

ICD-9-CM
754.69 Cong valgus foot def NEC
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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About Q66.6Overview

Is Q66.6 (Congenital deformities of feet) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other congenital valgus deformities of feet on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does Q66.6 group to?

When other congenital valgus deformities of feet is the principal diagnosis on an inpatient stay, it groups to MS-DRG 564, 565, 566, with relative weights from 0.7493 to 1.5436 depending on complications. Higher weights mean higher Medicare reimbursement.

Is Q66.6 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 other congenital valgus deformities of feet on inpatient claims.

What is the ICD-9 equivalent of Q66.6?

Under the General Equivalence Mappings, other congenital valgus deformities of feet converts to ICD-9-CM 754.69 (cong valgus foot def NEC). The mapping is a direct match.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.