Coding References

CPT® Resources

• AMA CPT® Overview – Learn how CPT codes are created, maintained, and updated by the American Medical Association.

• E/M Services Guide (CMS) – A practical guide to coding Evaluation & Management services accurately.

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HCPCS Level II

• HCPCS Code Search (AAPC) – Quickly look up Level II codes with descriptors.

• CMS Alpha-Numeric HCPCS File – Direct link to the official HCPCS Level II code sets.

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ICD-10-CM

• CDC ICD-10-CM Browser Tool – Search ICD-10-CM codes with official descriptions.

• ICD-10 Training Modules (WHO) – Free resources from the World Health Organization on coding and classifications.

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Modifiers

• AAPC — What Are Medical Coding Modifiers? - Overview, examples, and quick references.

• AAPC — CPT® Modifiers Index

• CMS — Global Surgery Booklet (ICN MLN907166) - Current PDF with modifier 25/57 guidance in global periods.

• CMS — Proper Use of Modifiers 59, XE, XP, XS & XU (Fact Sheet)

• CMS — How to Use the Medicare NCCI Tools (MLN901346) - Includes when 59/X{E,P,S,U} apply with PTP edits.

• CMS — Medicare Claims Processing Manual (Modifier 25 language)