How To Apply CPT Codes For IV Infusions
How to code IV Infusion Guide
IV infusion coding is time-based and must meet strict minimum time thresholds to be separately reportable. Accurate IV infusion coding requires proper documentation of start and stop times, medical necessity, and correct CPT code selection. To solve the billing requirements for IV infusion in the ED and OBV workflow, we must follow a logical step-by-step process tailored to facility-based reporting.
96365 – Initial IV infusion, up to 1 hour
96366 – Each additional hour of IV infusion
96367 – Sequential IV infusion (different medication)
96368 – Concurrent IV infusion
The rules for infusion coding are just outright confusing. Below is a list of rules that are best practice to avoid denial and stay compliant with CPT guidelines.
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IV Infusion is ranked above an IVP, IM/SubQ and Hydration. This mean no matter what if at any time during the patients encounter a billable IV infusion is administered will be billed as the initial 96365.
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IV Infusion must be <16 mins. An infusion that is only 15 mins is billed as IVP.
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Only one "initial" IV infusion code is permitted per vascular access site per encounter. In OBV settings where a patient may stay for 24 hours, only one 96365 is billed unless a second IV site is medically necessary and documented.
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The 31-Minute Rule: An additional unit of 96366 is only billable if the IV infusion continues for at least 31 minutes into the next hour. Calculation Logic:
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16-90minutes=96365×1
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91-150minutes=96365×1and96366×1
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151-210minutes=96365×1and96366×2
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If a patient starts in the emergency room and their status changes to inpatient all medications are a hard stop meaning they do not roll over to the inpatient encounter. However, if a patient starts in the emergency room and goes to observation they roll over so an infusion started in the ER is billed on the ER level but can continue into observation. More on ER to OBV status change.
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Make the MAR your friend. Understanding the MAR is non-negotiable, understand what the MAR really is or how to read the MAR
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All three add-on codes (96366, 96367, 96368) can never stand alone; they must always be reported alongside an initial code (96365)
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What counts as "therapeutic"? Antibiotics, iron infusions, steroids, antivirals, antifungals, biologics, pain medications, electrolyte replacement. If a drug is mixed into saline, the entire bag is coded as therapeutic (the fluid is considered incidental hydration).
A good way to look at IV Infusion Coding is
Frist drug, first hour 96365 "The main event starts"
Same drug runs longer 96366 "Keep the same drip going"
Different drug, one after another 96367 "Swap to a new drug, same line"
Different drug, at the same time 96368 "Hang a second bag alongside"
ED + Observation = One Encounter
This is the single most important concept for facility outpatient infusion billing.
Per the CMS Billing Manual, drug administration services are reported with the date of service on the day they are provided.
Only one initial drug administration service is reported per vascular access site per encounter, including during an encounter where observation services span more than one calendar day.
What this means in practice:
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Patient arrives in ED at 8 PM, starts IV Zosyn → code 96365 (initial)
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Patient moves to observation at midnight, Zosyn continues → code 96366 for additional hours only; do NOT code 96365 again
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If hydration started in the ED and is the only injection/infusion service, bill the initial hydration only once across the entire ED-to-observation encounter
To get a complete breakdown of the MAR in Epic click here
INITIAL ADMINISTRATION (96365)
What it really means:
This is the main infusion through that IV site.
It must:
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Run at least 16 minutes
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Be the highest hierarchy service at that site
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Be reported only once per IV site per encounter
Simple way to think of it:
If you start an IV and hang a therapeutic drug —
that drug is your initial administration.
Even if:
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Another drug is started later
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The patient moves from ED to observation
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Midnight passes
You DO NOT get another initial unless:
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You start a new IV site
ADDITIONAL HOUR (96366)
What it really means:
The same infusion keeps running beyond the first hour.
This code:
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Can ONLY exist if you already billed an initial
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Is time-based
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Requires at least 31 minutes into the next hour to bill another unit
Simple way to think of it:
Hour 1 → Initial
Hour 2+ → Additional hour(s)
It’s just time extension of the same drug.
Nothing new. Just more time.
SEQUENTIAL ADMINISTRATION (96367)
What it really means:
A different drug is infused AFTER (or temporarily pauses) the initial drug — using the same IV site.
Key idea:
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One drug finishes or pauses
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Another drug starts
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Same IV line
That is sequential.
Requirements:
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Must run at least 16 minutes
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Must be a different drug
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Must not run at the same time
Simple way to think of it:
Drug A → then Drug B
One after the other
Same IV
That’s sequential.
CONCURRENT ADMINISTRATION (96368)
What it really means:
Two different therapeutic infusions running at the SAME TIME through the SAME LINE.
Key idea:
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Drug A is running
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Drug B starts
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Both are infusing simultaneously
That’s concurrent.
KEY NOTE:
If a different drug is running at the SAME TIME, DIFFERENT LINE It is coded as 96365 - 59
Important:
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No add-on hours for concurrent
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Packaged under OPPS for facilities (not separately paid)
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Still must be coded correctly
Simple way to think of it:
Drug A + Drug B
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Running together
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Same IV line
That’s concurrent.
The Part Most People Mess Up
Concurrent vs Separate IV Sites
If:
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Drug A runs in left arm
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Drug B runs in right arm
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At the same time
That is NOT concurrent.
That may qualify for a separate initial administration because it is a separate vascular access site.
Concurrent only applies when medications share the SAME line.
The Mental Formula
Ask yourself in this order:
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Is this the main infusion at this IV site? → Initial
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Is it the same drug continuing past an hour? → Additional hour
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Is it a different drug given after the first one? → Sequential
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Is it a different drug running at the same time? → Concurrent
Click here for a walk through of a real scenario
