What Modifier 24 Means
When a surgeon does a procedure, the normal follow-up visits are part of the surgical payment. That window is the global period: 10 days for minor procedures and 90 days for major ones.
Modifier 24 tells the payer that an E/M visit by the same physician, or the same group and specialty, during that window was for a different problem. With the modifier and the right diagnosis, the visit is paid on its own.
Look up the global days for any code with our global period calculator.
When to Use Modifier 24
| Situation | Code it like this |
|---|---|
| Knee replacement (27447, 90-day global). Six weeks later the patient sees the same surgeon for new shoulder pain. | E/M visit + modifier 24, with the shoulder diagnosis |
| Lesion excision (11402, 10-day global). On day 5 the patient comes in with an unrelated rash. | E/M visit + modifier 24, with the rash diagnosis |
| Knee arthroscopy (29881, 90-day global). The surgeon also manages the patient's ongoing gout in the other foot. | E/M visit + modifier 24, with the gout diagnosis |
When Not to Use Modifier 24
- Routine follow-up after the surgery. It is already paid. Some practices log it with 99024 at no charge to track it.
- Care for a complication of the surgery. Medicare includes this in the global period unless the patient returns to the operating room.
- A visit on the day of a minor procedure. Use modifier 25 if the visit was separate and significant.
- The visit where you decided to do major surgery. Use modifier 57 on that visit.
Modifier 24 vs Other Global Period Modifiers
| Modifier | Use it for |
|---|---|
| 24 | An unrelated E/M visit during the global period |
| 25 | A separate E/M on the same day as a minor procedure |
| 57 | The visit where the decision for major surgery was made (day before or day of) |
| 58 | A planned or staged procedure during the global period |
| 78 | A return to the operating room for a complication |
| 79 | An unrelated procedure during the global period |
Medicare Rules
Medicare explains what the global surgery payment includes in its Claims Processing Manual, Chapter 12, Section 40. Visits for problems unrelated to the surgery are not included and can be paid with modifier 24. The diagnosis on the claim, and the note, should make the difference clear.
Payers often ask for records on modifier 24 claims. If the note reads like a routine post-op check, expect a denial such as CO-97 (the service is included in another service).
Documentation Checklist
- A chief complaint and diagnosis that are clearly not the surgical problem.
- An assessment and plan for that new problem.
- A separate note, or a clearly separate section, from any post-op check done the same day.
- The visit level supported by medical decision making or total time.
Frequently Asked Questions
Reviewed by Hassan Raza Awan, Founder — 4+ years of hands-on U.S. medical billing experience. General billing information — verify against current CMS guidance and your payer contracts.
Visit on the day of or the day before a major surgery, where you decided to operate? That is modifier 57.
Global Period Visits Going Unpaid?
We track global periods and apply modifiers 24, 25, 57, 58, 78 and 79 correctly on every surgical claim. The first week is free.
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