2027 ICD-10-CM Diagnosis Code Q66Congenital deformities of feet

ICD-10-CM Codes›Q00-Q99›Q65-Q79›Q66

ICD-10-CM Q66
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

Q66 is a non-billable ICD-10-CM category code for congenital deformities of feet, so it cannot be submitted on claims. Use a more specific code from this category instead, such as Q66.00, Q66.01, Q66.02, and Q66.10.

Code Identity

ICD-10-CM Code
Q66
Billable Status
No — Non-Billable Category
Code Describes
Congenital deformities of feet
Short Description
Congenital deformities of feet
Same as the full description in the CMS dataset.
Chapter
Q65-Q79
Congenital malformations and deformations of the musculoskeletal system

Code Classification

ChapterQ00-Q99Congenital malformations, deformations and chromosomal abnormalities
SectionQ65-Q79Congenital malformations and deformations of the musculoskeletal system
CategoryQ66Congenital deformities of feet
This CodeQ66Congenital deformities of feet

Specific Coding for Congenital deformities of feetOverview

Non-specific codes like Q66 require more characters. Use one of these billable codes instead:

  • Q66.0 for Congenital talipes equinovarus

  • Use Q66.00 for Congenital talipes equinovarus, unspecified foot

  • Use Q66.01 for Congenital talipes equinovarus, right foot

  • Use Q66.02 for Congenital talipes equinovarus, left foot

  • Q66.1 for Congenital talipes calcaneovarus

  • Use Q66.10 for Congenital talipes calcaneovarus, unspecified foot

  • Use Q66.11 for Congenital talipes calcaneovarus, right foot

  • Use Q66.12 for Congenital talipes calcaneovarus, left foot

  • Q66.2 for Congenital metatarsus (primus) varus

  • Q66.21 for Congenital metatarsus primus varus

  • Q66.22 for Congenital metatarsus adductus

  • Q66.3 for Other congenital varus deformities of feet

  • Use Q66.30 for Other congenital varus deformities of feet, unspecified foot

  • Use Q66.31 for Other congenital varus deformities of feet, right foot

  • Use Q66.32 for Other congenital varus deformities of feet, left foot

  • Q66.4 for Congenital talipes calcaneovalgus

  • Use Q66.40 for Congenital talipes calcaneovalgus, unspecified foot

  • Use Q66.41 for Congenital talipes calcaneovalgus, right foot

  • Use Q66.42 for Congenital talipes calcaneovalgus, left foot

  • Q66.5 for Congenital pes planus

  • Use Q66.50 for Congenital pes planus, unspecified foot

  • Use Q66.51 for Congenital pes planus, right foot

  • Use Q66.52 for Congenital pes planus, left foot

  • Use Q66.6 for Other congenital valgus deformities of feet

  • Q66.7 for Congenital pes cavus

  • Use Q66.70 for Congenital pes cavus, unspecified foot

  • Use Q66.71 for Congenital pes cavus, right foot

  • Use Q66.72 for Congenital pes cavus, left foot

  • Q66.8 for Other congenital deformities of feet

  • Use Q66.80 for Congenital vertical talus deformity, unspecified foot

  • Use Q66.81 for Congenital vertical talus deformity, right foot

  • Use Q66.82 for Congenital vertical talus deformity, left foot

  • Use Q66.89 for Other specified congenital deformities of feet

  • Q66.9 for Congenital deformity of feet, unspecified

  • Use Q66.90 for Congenital deformity of feet, unspecified, unspecified foot

  • Use Q66.91 for Congenital deformity of feet, unspecified, right foot

  • Use Q66.92 for Congenital deformity of feet, unspecified, left foot

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to Q66: its own notes plus those printed at Chapter 17. A note printed at a category, block or chapter applies to every code under it.

Excludes1

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

  • reduction defects of feet (Q72.-)
  • valgus deformities (acquired) (M21.0-)
  • varus deformities (acquired) (M21.1-)

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 Q66, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming Q66: they are not reported together with it, unless the two conditions are unrelated.

  • M20 Acquired deformities of fingers and toes
    congenital deformities and malformations of fingers and toes (Q66.-, Q68-Q70, Q74.-)
  • M21 Other acquired deformities of limbs
    congenital deformities and malformations of limbs (Q65-Q66, Q68-Q74) names Q65-Q66, which includes this code

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.

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 Q66Overview

What is the ICD-10 code for congenital deformities of feet?

Q66 is the ICD-10-CM category for congenital deformities of feet, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

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

No. This is a category header that groups the codes for congenital deformities of feet, and headers cannot be submitted on claims. Claims for congenital deformities of feet need a more specific code from this category, such as Q66.00, Q66.01, and Q66.02.

Can Q66 be reported with a code from Q72?

Not as a rule. The Excludes1 note on Q66 lists "reduction defects of feet (Q72.-)". 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).