E/MMedium audit riskCPT

CPT Modifier 24

Unrelated Evaluation and Management Service by the Same Physician or Other Qualified Health Care Professional During a Postoperative Period

Source: AMA CPT / CMS HCPCS Level II definitions. Maintained by the D3rx Clinical Billing Team.

What modifier 24 means

Modifier 24 is appended to an E/M service performed during a procedure's global period when the visit is unrelated to the surgery that established the global period. It allows separate payment for care that falls outside the global surgical package.

When to use it

A patient within a surgery's postoperative global period is seen by the same physician for an unrelated problem — for example, a patient in a 90-day knee-surgery global presents for an upper respiratory infection.

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Documentation checklist

The record should support every item below before you append modifier 24.

  • That the E/M is unrelated to the procedure that set the global period
  • A clearly unrelated diagnosis supporting the separate reason for the visit
  • That the global period was in effect on the date of service

Do NOT use modifier 24 when

  • The visit is routine postoperative care (bundled in the global package)
  • The E/M is related to the original surgery or its complications
  • It is a same-day-as-procedure significant E/M — use modifier 25

Common denial reasons

  • The diagnosis appears related to the surgery
  • Documentation does not establish an unrelated reason for the visit
  • The global period was not actually active

Denial codes you may see with modifier 24

CO-97CO-4CO-50

How to appeal a modifier 24 denial

Provide the office note and an ICD-10 that is clearly unrelated to the surgical diagnosis, demonstrating the visit addressed a separate problem rather than routine post-op follow-up. Note the global period and that this E/M is not part of the surgical package.

Payer notes

A different ICD-10 from the surgical diagnosis strengthens a modifier 24 claim, and payers may request the office note. Global periods follow the CMS global-days indicator for the procedure.

Related & commonly confused modifiers

Modifier 25Modifier 57Modifier 79Modifier 58Modifier 78

Where modifier 24 is used

  • Office/outpatient E/M (99211–99215, 99202–99205) during a surgical global period
  • Subsequent hospital care E/M during a global period

Look up these codes & their 2026 Medicare rates

99211992159920299205

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Medical billing disclaimer

Modifier definitions follow standard AMA CPT and CMS HCPCS Level II guidance and are for educational reference. Payer policies, billing formats, and coverage rules vary and change. Always verify the current rule with the specific payer before submitting. D3rx is not responsible for claim outcomes.