ICD-10 Q66
Non-Billable HeaderCongenital deformities of feet
About ICD-10-CM Q66
ICD-10-CM code Q66 represents Congenital deformities of feet. This is a non-billable header code in the Congenital Malformations chapter (block Q66). The 2026 edition of ICD-10-CM Q66 became effective on October 1, 2025. Non-billable codes cannot be used as a primary or secondary diagnosis on a claim, use a more specific child code instead.
Type 1 Excludes
Pure excludes, these codes can never be coded together with Q66. The conditions are mutually exclusive (e.g., congenital vs acquired forms).
- reduction defects of feet (Q72.-)
- valgus deformities (acquired) (M21.0-)
- varus deformities (acquired) (M21.1-)
Medicare LCD Coverage for Q66
Local Coverage Determinations (LCDs) from CMS MACs that list Q66 as a covered diagnosis.
This doesn't mean the code isn't covered, it means no MAC has issued a Local Coverage Determination naming this specific code. Coverage may still apply under National Coverage Determinations or general medical-necessity rules.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing Q66.
Our payer policy database covers Aetna, Cigna, Anthem, BCBS, Humana, and Medicare Advantage plans, but Q66 doesn't currently appear in any indexed policy. The code may still be covered under standard plan benefits.
CPT Codes Commonly Billed with Q66
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
We don't have CPT pairings indexed for this specific code yet. Use the CPT search above to find common procedures, or check your payer's published medical policy for code-specific guidance.
Codes Adjacent To Q66
Other codes in section Q65-Q79 (Congenital malformations and deformations of the musculoskeletal system).
ICD-10 Q66, Billing FAQ
Is ICD-10 code Q66 billable? +
No, Q66 is a non-billable header code. Use a more specific child code from block Q66 when submitting claims.
What codes are Type 1 Excludes for Q66? +
Type 1 Excludes (never code together with Q66): reduction defects of feet (Q72.-); valgus deformities (acquired) (M21.0-); varus deformities (acquired) (M21.1-)
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on June 1, 2026.
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