Modifier AJ
Clinical social worker — service furnished by a clinical social worker
✅ When to Use Modifier AJ
Append to professional services furnished by a CSW when payer requires identification
⛔ When NOT to Use Modifier AJ
Do not use for clinical psychologists (AH)
Modifier AJ FAQ
What does modifier AJ mean? +
Clinical social worker — service furnished by a clinical social worker
When should I use modifier AJ? +
Append to professional services furnished by a CSW when payer requires identification
When should I NOT use modifier AJ? +
Do not use for clinical psychologists (AH)
What documentation is required for modifier AJ? +
Complete chart documentation supporting the modifier's clinical or billing rationale.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on April 19, 2026.
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