Modifiers 73 and 74: The Facility Side of an Abandoned Case

Modifiers 73 and 74 exist because a hospital outpatient department or an ambulatory surgery centre can consume most of the cost of a case that never happened. Staff were assigned, a room was held, the patient was prepped, drugs and supplies were opened. CMS created the two modifiers so that expenditure could be recognised on a claim even though the procedure was abandoned.

They are the facility-side counterparts to modifiers 52 and 53, and the single most useful thing to understand about them is that they do not correspond to the professional modifiers one-for-one. The facility modifier is chosen by where the case stopped relative to anesthesia. The physician modifier is chosen by whether the physician’s own work was reduced or terminated. Those are different questions about the same abandoned case, and they routinely produce a facility claim and a professional claim that look nothing alike. That is expected. This guide explains why, and what each side is actually entitled to.

The Decision Rule: Three Points on One Timeline

Chapter 4 of the Medicare Claims Processing Manual (Publication 100-04), Section 20.6.4, and the parallel ASC instruction at Chapter 14, Section 40.4, describe the same timeline. Find where the case stopped on it, and the facility modifier follows.

Point 1 — before the patient reaches the room: nothing is billable

Chapter 14, Section 40.4.A is blunt: contractors deny payment when an ASC submits a claim for a procedure terminated before the patient is taken into the treatment or operating room. The manual’s own example is a case cancelled or postponed because the patient, on intake, complains of a cold or flu. Chapter 4 states the same limit for hospital outpatient billing in one line: "the elective cancellation of a procedure should not be reported."

This is the boundary practices lose the most money arguing about, and it is not arguable. A case called off in pre-op holding, in the waiting room, or the night before is a non-event on both claims.

Point 2 — prepped, in the room, before anesthesia: modifier 73

Modifier 73 reports that a procedure requiring anesthesia was terminated because of extenuating circumstances or circumstances threatening the patient’s wellbeing, after the patient had been prepared for the procedure (including procedural pre-medication when provided) and taken to the room where the procedure was to be performed, but before anesthesia was administered.

Chapter 14 works two examples that show what a qualifying event looks like: the patient develops an allergic reaction to a drug the ASC administered before surgery, or, on injection of a retrobulbar block, suffers a retrobulbar haemorrhage that prevents the procedure continuing. Both are clinical events, not scheduling ones.

Payment: 50 percent of the full OPPS payment amount (Chapter 4, Section 20.6.4.B); 50 percent of the rate for an ASC (Chapter 14, Section 40.4.B). The manual gives the reasoning explicitly — some supplies and resources were expended, but not to the same extent as if anesthesia had been fully induced and the surgery completed.

Point 3 — after induction or after the procedure started: modifier 74

Modifier 74 reports termination after the induction of anesthesia or after the procedure was started. Chapter 4 gives concrete markers for "started": incision made, intubation started, scope inserted.

Payment: the full OPPS payment amount. Chapter 14’s example is a case where, after anesthesia and a preliminary incision, the patient’s blood pressure rises suddenly and the surgery is stopped to avoid increasing surgical risk. The rationale, again stated in the manual: the facility’s resources "are consumed in essentially the same manner and to the same extent as they would have been had the surgery been completed."

The definition of "anesthesia" here is wider than most people assume

For hospital outpatient billing, Chapter 4 defines anesthesia for this purpose to include local, regional block(s), moderate sedation or analgesia ("conscious sedation"), deep sedation or analgesia, and general anesthesia. A case planned under a local block is a case with anesthesia planned. Treating "anesthesia" as meaning general anesthesia is the most common way a facility ends up on modifier 52 when it should have been on 73.

The rule that decides 73/74 versus 52 on a facility claim

Chapter 4 draws the line in a single sentence: "Modifiers 73 and 74 are only used to indicate discontinued procedures for which anesthesia is planned or provided." Where anesthesia was not planned and the procedure is discontinued after the patient is prepared and taken to the room, the facility reports modifier 52 — and is paid at 50 percent of the full OPPS amount, the same figure as modifier 73. Chapter 14, Section 40.4.F confirms the same treatment for ASCs from 1 January 2008, specifically naming discontinued radiology procedures and other procedures not requiring anesthesia.

Why the Facility and Professional Claims Will Not Match

The 52-versus-53 guide sets out the physician-side rules and lines the four modifiers up against each other. This section does the other half of the job: it takes one abandoned case and follows it onto both claims.

Where the case stopped	Facility claim (HOPD / ASC)	Facility payment	Physician claim	Physician payment
Cancelled before the patient reached the treatment or procedure room	Nothing	Denied — elective cancellation is not reportable	Nothing for the procedure	—
Prepped and in the room; anesthesia planned; stopped before anesthesia	73	50 percent of the full OPPS/ASC amount	Usually nothing — the procedure was not started	—
Anesthesia induced, or procedure started (incision, intubation, scope), then stopped	74	Full OPPS/ASC amount	53	Reduced charge reflecting what was done
After anesthesia, discontinued or partially reduced at the physician’s discretion	74	Full OPPS/ASC amount	52 (deliberate reduction) or 53 (termination)	By report / reduced charge
Anesthesia never planned; prepped, in the room, discontinued	52	50 percent of the full OPPS/ASC amount	52, or a code describing what was actually done	Individual consideration on documentation

Three asymmetries fall out of that table, and each one is a live source of confusion.

1. Modifier 74 pays the facility in full while the physician is paid less

This is the sharpest one. On the same abandoned case, Chapter 4 pays the facility the full OPPS amount — and the physician’s modifier 53 claim is expected to carry a reduced charge, because Medicare’s claims processing system does not reduce a modifier 53 payment automatically; the biller does it. So a coder reconciling the two claims sees the hospital paid at 100 percent and the surgeon paid at a fraction, for the same aborted operation.

Nothing is wrong. They are paying for different things. The OPPS amount buys the room, the staff, the recovery bay and the supplies, all of which were consumed. The professional fee buys the surgeon’s work, which was not.

2. Modifier 52 means two different things depending on which claim it sits on

On a facility claim, modifier 52 is a fixed rule tied to a position on the timeline: anesthesia not planned, patient prepped and in the room, procedure discontinued → 50 percent of the full OPPS amount. It is mechanical.

On a professional claim, modifier 52 is nothing of the kind. Chapter 12, Section 40.4 prices it by individual consideration on the strength of a concise statement plus the operative report, and states that "pricing for ‘-52’ is not done without the required documentation" — the claim does not price at all. Same two digits, two entirely different rulebooks. A billing team that has internalised the facility version and then applies it on the Part B side submits claims that never price.

3. The facility asks about anesthesia; the physician asks whether work started

Chapter 4 draws the facility boundary exactly at the moment of anesthesia. The physician modifiers are not tied to that threshold at all — contractor guidance describes modifier 53 as available where a procedure was started and discontinued "prior to or after anesthesia is administered." Consistent in principle, but the practical result is the one this page exists to state: the professional and facility claims for a single abandoned case will legitimately carry non-corresponding modifiers, and a reconciliation report that flags every mismatch as an error will flag correct claims.

A fourth, quieter one: 74 is the modifier that can still be cut

Chapter 14, Section 40.4.G provides that ASC surgical services billed with modifier 52 or modifier 73 are not subject to the multiple procedure discount. Section 40.5 then adds that payment for an ASC surgical procedure billed with modifier 74 may be subject to the multiple procedure discount if that procedure is subject to it. So the modifier that pays in full is also the only one of the three exposed to a further reduction — an inversion worth knowing before an appeal is written.

The Payment Adjustments That Sit On Top

Device-intensive procedures with modifier 73

Modifier 73 does not always pay half. From 1 January 2016, for device-intensive procedures appended with modifier 73, CMS reduces the APC payment amount by 100 percent of the device offset amount before applying the discontinued-procedure adjustment. On a device-heavy case, that sequencing matters far more than the 50 percent does.

The definition of "device-intensive" has moved three times, and Chapter 4 records all three: for 1 January to 31 December 2016, procedures involving implantable devices assigned to a device-intensive APC (an APC with a device offset above 40 percent); from 1 January 2017, procedures requiring insertion of an implantable device with a HCPCS-level device offset above 40 percent; from 1 January 2019, procedures involving the surgical implantation or insertion of an implantable device assigned a CPT or HCPCS code (including single-use devices) with a device offset exceeding 30 percent of the procedure’s mean cost. Which definition applies depends on the date of service.

Intraocular lenses in a terminated ASC case

Chapter 14 records a change that still surfaces in old appeals: before 1 January 2008, contractors deducted the allowance for an unused IOL before calculating payment for a terminated IOL insertion. From 1 January 2008, payment for the IOL is included in payment for the surgical procedure to implant it.

What the Record Must Show

Chapter 14, Section 40.4 is unusually specific about the ASC operative report for a terminated case. The report is kept on file and produced if the contractor asks, and it should specify:

• the reason for termination of the surgery;
• the services actually performed;
• the supplies actually provided;
• the services not performed that would have been performed had the surgery not been terminated;
• the supplies not provided that would have been provided;
• the time actually spent in each stage — pre-operative, operative, post-operative;
• the time that would have been spent in each stage had the surgery not been terminated; and
• the HCPCS code for the procedure had the surgery been performed.

That list is worth reading as a template rather than a checklist. It asks for a counterfactual: what was consumed, and what would have been. A note recording only "case aborted" answers none of the eight and leaves a reviewer unable to distinguish a clinical termination from a cancellation.

Two more things the record has to make findable:

• The position on the timeline. Whether the patient had reached the procedure room, and whether anesthesia had been administered, are the two facts that select the modifier. If the anesthesia record and the nursing note disagree about the sequence, the claim is indefensible whichever modifier was used.
• That the termination was clinical. Extenuating circumstances or a threat to the patient’s wellbeing. A discretionary post-induction discontinuation is still modifier 74 under Chapter 4, but the note should say what the physician’s reasoning was rather than leaving a reviewer to infer that the case was simply called off.

The Misuse That Triggers Denials and Audits

1. Billing a case that never reached the room. Denied on the ASC side by an explicit instruction, and not reportable on the hospital side. This is the single largest category.
2. Using modifier 52 because the case was under a local block. Local and regional blocks and moderate sedation are all "anesthesia" for this purpose. Anesthesia planned means 73 or 74, not 52.
3. Putting modifier 53 on a facility claim. Chapter 4 states that modifier 53 indicates discontinuation of physician services and is not approved for use for outpatient hospital services. It is not a stricter version of 74; it belongs on the other claim entirely.
4. Using modifier 74 for a reduced-but-completed procedure. Where the intended service was performed at less than its full extent and finished, that is a reduced service, not a discontinued one — and the first question is whether a code describes what was actually done. Chapter 4’s radiology instruction generalises: code to the extent of the procedure performed, and reach for a modifier only where no code fits.
5. Assuming 73 pays half on a device-intensive case. The device offset comes off first.
6. Reconciling the two claims by expecting matching modifiers. They will not match. See the table above.
7. Treating 73/74 as bundling-edit tools. They are not among the modifiers that release a National Correct Coding Initiative procedure-to-procedure edit. A case that was abandoned still has to be coded correctly against the edits; if a pair genuinely represents distinct work, that is a modifier 59 or X{EPSU} question and a separate one.

Where Jurisdiction Matters, and Where Guidance Diverges

One divergence is worth naming rather than smoothing over. Chapter 4 and Chapter 14 both describe 73 and 74 as facility modifiers, and pay modifier 74 at the full amount. Noridian’s Part B modifier 74 page, however, illustrates the modifier appended to an anesthesia code with a reduced charge — a worked example showing a $200 allowed amount billed at $120 where 60 percent of the service was performed. Those are two different claims being described under one modifier number. Where a MAC’s own page and the manual appear to point in different directions about which claim carries the modifier, follow the MAC for that jurisdiction and expect the two claims for one case to look different on their face.

Beyond that, the usual scope limits apply, and they are sharper here than for most modifiers:

• The percentages are set in annual rulemaking. The 50 percent and full-payment treatments, the device-intensive threshold and the list of procedures subject to the ASC multiple procedure discount are all products of the OPPS/ASC final rule for the relevant payment year. Chapter 14 says so directly about the discount list. Check the current year’s rule before relying on any figure here.
• MAC guidance differs in emphasis. Noridian, Novitas and First Coast Service Options all publish pages on these modifiers and they do not read identically, particularly on what documentation is requested up front rather than held on file.
• Commercial and Medicare Advantage payers adopt the CPT convention but write their own edits and their own percentages. Several apply a flat percentage to both 73 and 74 rather than the OPPS split. Verify against the plan’s policy.

Frequently Asked Questions

What is the difference between modifier 73 and modifier 74?

When the case stopped relative to anesthesia. Modifier 73 reports a procedure requiring anesthesia that was terminated after the patient was prepared and taken to the procedure room but before anesthesia was administered. Modifier 74 reports termination after induction of anesthesia or after the procedure was started. Under OPPS, 73 pays 50 percent of the full payment amount and 74 pays the full amount.

Can a physician bill modifier 73 or 74?

These are facility modifiers for hospital outpatient departments and ASCs. The physician’s discontinued-procedure modifier is 53, and Chapter 4 states that modifier 53 is not approved for use for outpatient hospital services. Note that at least one MAC’s Part B guidance illustrates modifier 74 on a professional anesthesia claim, so confirm the position in your own jurisdiction.

Does "anesthesia" mean general anesthesia?

No. For hospital outpatient billing, Chapter 4 defines it to include local, regional blocks, moderate sedation or analgesia, deep sedation or analgesia, and general anesthesia. A case planned under a local block is a case with anesthesia planned, so 73 or 74 applies rather than 52.

What if the procedure never required anesthesia?

Then 73 and 74 do not apply. A procedure for which anesthesia was not planned, discontinued after the patient was prepared and taken to the room, is reported with modifier 52 and paid at 50 percent of the full OPPS payment amount.

Can we bill anything if the case was cancelled before the patient went to the room?

No. Contractors deny an ASC claim for a procedure terminated before the patient is taken into the treatment or operating room, and Chapter 4 states that the elective cancellation of a procedure should not be reported. Separately payable services genuinely furnished that day are billed on their own merits.

Does modifier 73 always pay 50 percent?

Not on a device-intensive procedure. From 1 January 2016, CMS reduces the APC payment by 100 percent of the device offset amount before applying the discontinued-procedure adjustment. The definition of a device-intensive procedure has changed three times and depends on the date of service.

Why does the facility claim carry modifier 74 and the surgeon’s claim carry modifier 53?

Because the two claims answer different questions. The facility modifier turns on whether anesthesia had been given; the physician modifier turns on whether the physician’s own work was started and terminated. One abandoned case producing a 74 on the UB and a 53 on the CMS-1500 is the normal result, not a mismatch to be corrected.

Are 73 and 74 subject to the ASC multiple procedure discount?

Chapter 14 provides that ASC surgical services billed with modifier 52 or 73 are not subject to further pricing reductions, so the multiple procedure rules do not apply to them. Payment for an ASC surgical procedure billed with modifier 74 may be subject to the discount where that procedure is subject to it.

Related CASRAI Resources

• Modifier 52 vs 53 — the professional-claim half of the same decision
• Modifier 22: increased procedural services — the other modifier priced by individual consideration, and the one that still pays without documentation
• Modifier 78: the unplanned return to the operating room — for the case that has to be re-entered later
• Modifier 58: staged or related procedure — for the case that resumes as planned
• Modifier 58 vs 78 vs 79 — planned, unplanned or unrelated
• Modifiers 26 and TC — the other place the professional and facility claims split
• Modifiers 62 and 66: co-surgeons and surgical teams
• Modifier 50: bilateral procedures — where the ASC bilateral reporting rule differs again
• Condition code 44 — the other mid-encounter status change with its own paperwork trail
• The False Claims Act in billing

Sources: CMS Medicare Claims Processing Manual, Publication 100-04, Chapter 4, Section 20.6.4 (modifiers 73 and 74, Rev. 11937, effective 1 April 2023), including the anesthesia definition, the OPPS payment percentages and the device-intensive definitions; Chapter 14, Sections 40.4 (payment for terminated ASC procedures, Rev. 11793, effective 21 February 2023), 40.4.G and 40.5 (multiple procedure discount); Chapter 12, Section 40.4 (individual-consideration pricing for modifier 52); Noridian Healthcare Solutions modifier 73 guidance (last updated 13 November 2024) and modifier 74 guidance (last updated 9 May 2025). OPPS and ASC payment percentages, the device-intensive threshold and the list of procedures subject to the ASC multiple procedure discount are set in annual OPPS/ASC rulemaking — verify the current year before relying on any figure. CPT is a registered trademark of the American Medical Association; modifier meanings are described here in summary and the AMA’s descriptor text is not reproduced. General reference material, not coding advice for a specific claim — verify against your own MAC’s current guidance and the payer’s policy.