Congenital deformities of feet (Q66) ICD-10-CM
The Q66 code range covers congenital deformities of feet with 44 ICD-10-CM diagnosis codes. 32 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Codes in the Q66 Range 44 codes · 32 billable
- Q66 Congenital deformities of feetNon-billable
- Q66.0 Congenital talipes equinovarusNon-billable
- Q66.00 Congenital talipes equinovarus, unspecified foot
- Q66.01 Congenital talipes equinovarus, right foot
- Q66.02 Congenital talipes equinovarus, left foot
- Q66.1 Congenital talipes calcaneovarusNon-billable
- Q66.10 Congenital talipes calcaneovarus, unspecified foot
- Q66.11 Congenital talipes calcaneovarus, right foot
- Q66.12 Congenital talipes calcaneovarus, left foot
- Q66.2 Congenital metatarsus (primus) varusNon-billable
- Q66.21 Congenital metatarsus primus varusNon-billable
- Q66.211 Congenital metatarsus primus varus, right foot
- Q66.212 Congenital metatarsus primus varus, left foot
- Q66.219 Congenital metatarsus primus varus, unspecified foot
- Q66.22 Congenital metatarsus adductusNon-billable
- Q66.221 Congenital metatarsus adductus, right foot
- Q66.222 Congenital metatarsus adductus, left foot
- Q66.229 Congenital metatarsus adductus, unspecified foot
- Q66.3 Other congenital varus deformities of feetNon-billable
- Q66.30 Other congenital varus deformities of feet, unspecified foot
- Q66.31 Other congenital varus deformities of feet, right foot
- Q66.32 Other congenital varus deformities of feet, left foot
- Q66.4 Congenital talipes calcaneovalgusNon-billable
- Q66.40 Congenital talipes calcaneovalgus, unspecified foot
- Q66.41 Congenital talipes calcaneovalgus, right foot
- Q66.42 Congenital talipes calcaneovalgus, left foot
- Q66.5 Congenital pes planusNon-billable
- Q66.50 Congenital pes planus, unspecified foot
- Q66.51 Congenital pes planus, right foot
- Q66.52 Congenital pes planus, left foot
- Q66.6 Other congenital valgus deformities of feet
- Q66.7 Congenital pes cavusNon-billable
- Q66.70 Congenital pes cavus, unspecified foot
- Q66.71 Congenital pes cavus, right foot
- Q66.72 Congenital pes cavus, left foot
- Q66.8 Other congenital deformities of feetNon-billable
- Q66.80 Congenital vertical talus deformity, unspecified foot
- Q66.81 Congenital vertical talus deformity, right foot
- Q66.82 Congenital vertical talus deformity, left foot
- Q66.89 Other specified congenital deformities of feet
- Q66.9 Congenital deformity of feet, unspecifiedNon-billable
- Q66.90 Congenital deformity of feet, unspecified, unspecified foot
- Q66.91 Congenital deformity of feet, unspecified, right foot
- Q66.92 Congenital deformity of feet, unspecified, left foot
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the Q66 range.
Clubfoot
A deformed foot in which the foot is plantarflexed, inverted, and adducted.
Equinus Deformity
Plantar declination of the foot.
Flatfoot
Anomaly in which one or more of the arches of the feet are flat.
Hypertelorism
Abnormal increase in the interorbital distance due to overdevelopment of the lesser wings of the sphenoid.
Talipes
Deformity in which the foot is misaligned with respect to the TALUS in the ANKLE JOINT. While mostly congenital, as in CLUBFOOT, acquired deformities are included. Acquired talipedes are often associated with other foot deformities such as SYNDACTYLY and POLYDACTYLY.
Talipes Cavus
A foot deformity in which the arch of the foot is high and often the heel adducted.
About the Q66 Code Range
ICD-10 codes Q66 and its subcategories are specifically used for identifying and classifying congenital deformities of the feet. These codes cover a broad range of foot abnormalities present at birth, such as talipes equinovarus (clubfoot), talipes calcaneovarus, metatarsus varus, pes planus (flatfoot), pes cavus (high arch), and other varus or valgus deformities affecting the feet.
This code set helps medical coders distinguish between different conditions by specifying the location (right foot, left foot, unspecified) and type of deformity. For example, Q66.0 series captures various forms of congenital talipes equinovarus, often known as clubfoot or by synonyms like talipes equinus and cavovarus deformities. Similarly, Q66.2 and Q66.22 detail metatarsus primus varus and metatarsus adductus, terms linked to the inward turning of the front foot. Coders encountering terms like “hallux valgus due to metatarsus primus varus” can find precise matching codes here. Other codes such as Q66.5 refer to congenital pes planus, while Q66.7 indicate pes cavus. The comprehensive subdivision facilitates accurate documentation and billing for various complex congenital foot conditions, including rarer deformities listed under Q66.8 and Q66.9. Using the correct ICD-10 code for congenital foot deformities ensures clarity in diagnosis and treatment planning.
Questions About This Page
How many billable codes are in the Q66 range?
Of the 44 codes in this range, 32 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the Q66 range classify?
The range classifies congenital deformities of feet. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
