Global Period
A global period is the window of time after a surgery during which routine follow-up care is bundled into the surgical payment and cannot be billed separately. Medicare assigns each procedure a 0-day, 10-day, or 90-day global period; a 90-day global actually covers 92 days including the day before surgery.
- Set by
- CMS, per CPT code (MPFS indicator)
- Lengths
- 0, 10, or 90 days
- 90-day span
- 92 days total (day before + day of + 90 after)
- Escape hatch
- Modifiers 24, 25, 57, 58, 78, 79
What does the global period include?
The global surgical package bundles the procedure itself plus routine pre-op and post-op care into one payment. When Medicare pays for a knee arthroscopy, that check already covers the pre-op visit on the day of (or day before) surgery, the intraoperative work, and every routine follow-up visit inside the global window. Billing those visits separately gets you a CO-97 denial, because the payer considers them already paid.
Specifically included: post-op pain management, dressing changes, suture removal, incision checks, and complications that do not require a return trip to the OR. Not included: the initial visit where surgery was decided, unrelated problems, staged procedures, and treatment of complications in the operating room.
How long is a global period?
Medicare assigns one of three standard lengths to every surgical CPT code, and the math matters more than most people realize:
- 0-day (endoscopies, minor procedures): only the day of the procedure is bundled.
- 10-day (minor surgery, e.g., simple laceration repair): day of surgery plus 10 days, 11 days total.
- 90-day (major surgery, e.g., total knee replacement): day before surgery, day of, and 90 days after, 92 days total.
You will also see XXX (global concept does not apply, common on E/M and radiology), ZZZ (add-on codes that inherit the primary code's period), and MMM (maternity).
Can you bill anything during a global period?
Yes, when the service is genuinely separate, and the modifier tells the payer why. A patient 30 days out from a 90-day-global shoulder repair who comes in with bronchitis is billable: append modifier 24 to the E/M. An unplanned return to the OR for a post-op bleed takes modifier 78 (paid at roughly the intraoperative percentage of the fee). An unrelated procedure, like removing a skin lesion on the other arm, takes modifier 79 and restarts its own global period. The visit where the surgeon decides to operate the next day takes modifier 57 so it is not swallowed by the package.
See the full guide to global period modifiers for a decision chart covering 24, 25, 57, 58, 78, and 79.
What is the most common global period mistake?
Writing off denied post-op E/M visits without checking whether they were actually unrelated. Here is a real-world example: a general surgeon does a laparoscopic cholecystectomy (90-day global) on March 3. On April 10 the patient is seen for new-onset hypertension. The front desk books it as a "post-op check," the coder bills 99213 with no modifier, and the claim denies CO-97. That visit was payable, roughly a $100 allowable at the 2026 Medicare rate, and it only needed modifier 24 with a hypertension diagnosis. Multiply that by every surgeon in the practice and the leakage is real.
Frequently asked questions
Look up the code in the Medicare Physician Fee Schedule lookup tool on cms.gov and check the "Global" column. You will see 000, 010, or 090 for standard periods, plus XXX (concept does not apply), ZZZ (add-on code, follows the primary), YYY (carrier-priced), or MMM (maternity).
Yes. A 0-day global covers only the day of the procedure. A 10-day global covers the day of surgery plus 10 days after (11 days total). A 90-day global covers the day before, the day of, and 90 days after, so 92 days in total.
Only if the visit is unrelated to the surgery, or treats a new problem or complication requiring a return to the OR. Append modifier 24 to an unrelated E/M during the post-op period, modifier 79 to an unrelated procedure, and modifier 78 for an unplanned return to the operating room.
Most do, because they license the Medicare Physician Fee Schedule indicators. But a handful of payers and some Medicaid programs apply their own bundling windows, so check the payer policy before writing off a denied post-op visit as bundled.
Sources & further reading
Reviewed by the ImmediCare Solutions RCM team
Certified billers and coders handling claims across 50+ specialties nationwide. This entry is reviewed against current payer policy and CMS rules. Last review: Jul 5, 2026.
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