Add-on code for each additional hour of the same therapeutic, prophylactic, or diagnostic IV infusion after the first hour has been reported.
- Medicare
- $21.38
- Work RVU
- 0.18
- Global, days
- Region
- General
Documentation requirements
What must appear in the operative or office note to support the claim.
Source · Editorial brief grounded in 3 cited references ↓
- Infusion start and stop times showing total time of 91 minutes or more
- Same drug continuing from the initial or sequential infusion
- Primary code (96365 or 96367) billed on the same claim
- Reason the infusion rate required extended time
- Patient monitoring during the extended infusion
Applicable modifiers
Modifiers commonly billed with this code.
Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual
What this code covers
Source · Editorial summary grounded in 3 cited references ↓
96366 adds time to an IV infusion that runs past the first hour. It is an add-on, so it is billed with 96365 (initial infusion) or 96367 (sequential infusion), never alone.
The time rule is where people slip. The first hour covers up to 60 minutes. A second hour is billable only when the extra time is more than 30 minutes past the hour, so the infusion has to reach at least 91 minutes total. A 75-minute infusion is one unit of 96365 and nothing else.
In ortho, long infusions are uncommon but happen with some IV antibiotic regimens for bone and joint infections, and with slow-rate IV iron. Hydration time has its own add-on (96361), so use 96366 only for the drug infusion itself. Keep start and stop times in the record, because auditors recalculate the minutes.
RVU & reimbursement
Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.
Source · CMS Physician Fee Schedule, RVU26A · January 2026
Work RVU vs. total RVU
The work RVU (0.18) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (0.64) adds practice overhead and malpractice, and is what drives the Medicare payment below.
| Work RVU | 0.18 |
| Practice expense RVU | 0.45 |
| Malpractice RVU | 0.01 |
| Total RVU | 0.64 |
| Medicare national rate | $21.38 |
| Global period | days |
Payment by site of service
Medicare pays different rates by setting. HOPD typically pays substantially more than ASC for the same procedure.
Source · CMS OPPS Addendum B·ASC HCPCS payment rates·2026
| Setting | Medicare rate (national) |
|---|---|
Office (PFS non-facility) Procedure performed in physician's office | $21.38 |
HOPD (APC 5691) Hospital outpatient department | $47.84 |
Common denial reasons
The recurring reasons claims for CPT 96366 get rejected.
Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓
- Billed without a primary infusion code
- Total time under 91 minutes
- No stop time recorded
- Used for hydration time instead of 96361
- Units overstate the documented time
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 3 cited references ↓
01When can I bill 96366?
02Can 96366 be billed without 96365?
03Is 96366 used for hydration time?
Sources & references
Editorial content was developed using the following public sources.
Mira Scribe
Mira Scribe captures infusion start and stop times in the note, which is the first thing an auditor checks when 96366 is billed.
See how Mira captures CPT 96366 documentation