• Coding Basics

    HCPCS Codes

    HCPCS allows physicians to document the services provided. These codes are added to insurance claims and submitted to insurance companies for payment.

    Accurate and appropriate coding for the services you provide in your practice is vital, not only for payment purposes, but also for documentation purposes.Many electronic health records (EHRs) and medical billing systems can produce reports based on the Healthcare Common Procedure Coding System (HCPCS) data that can help practices identify gaps in care for their patients.

    HCPCS Level I: About Current Procedural Terminology (CPT) Codes

    • Describe medical, surgical, diagnostic, and other types of services
    • Owned and maintained by American Medical Association (AMA)
    • Numeric and alpha-numeric codes consisting of 5 characters
    • Each code begins with a numeric character
    • There are 2-digit modifiers available to indicate a service has been altered by some specific circumstance, anatomical location that does not alter the service or to address payment policy requirements of other entities.


    • 99204 New Patient Level 4 Evaluation and Management (E/M) Code
    • - 25 Modifier for significant, separately identifiable E/M service by the same physician on the same day

    HCPCS Level II: About Codes Not Included in CPT

    Often pronounced by its acronym as "hick picks," HCPCS is a set of health care procedure codes.

    • Identify products, supplies, and services
    • Maintained by the Centers for Medicare & Medicaid Services
    • Alpha-numeric codes consisting of 5 characters
    • Each code begins with an alpha character
    • There are 2-character modifiers available


    • G0008 Administration of influenza virus vaccine
    • AJ Clinical Social Worker (CSW)
    • F1 Left Hand, Second Digit


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    ICD-10 Codes

    ICD-10-CM (International Classification of Diseases, 10th Revision, Clinical Modification) is a set of codes to report the reason(s) for patient encounters and certain patient characteristics. ICD-10 Codes are placed on health insurance claims to convey to insurance companies the reason for the encounter. As with HCPCS codes, ICD-10 codes can be used for reporting purposes, such as identifying cohorts of patients with the same condition. Understanding the common diagnoses within your practice can help focus quality improvement and population health efforts.

    • Describe diagnoses, signs, symptoms, and other reasons for an encounter (e.g. prevention, counseling)
    • Includes codes to describe certain patient characteristics (e.g., body mass index)
    • Maintained by an interdepartmental committee comprised of representatives from the Centers for Medicare and Medicaid Services (CMS) and the Centers for Disease Control and Prevention's (CDC) National Center for Health Statistics (NCHS)
    • Alpha-numeric codes of 3 to 7 characters
    • Each code begins with an alpha character


    • E11.42 Type 2 diabetes with diabetic polyneuropathy
    • E10.649 Type 1 diabetes with hypoglycemia without coma
    • I50.42 Chronic combined systolic and diastolic congestive heart failure