Glossary · Reimbursement

HOPD (hospital outpatient department)

A hospital outpatient department (HOPD) is a facility owned and operated by a hospital that provides outpatient services billed under Medicare's Hospital Outpatient Prospective Payment System (OPPS), typically reimbursed at higher rates than the same service performed in a freestanding physician office.

Verified May 8, 2026 · 6 sources ↓

Drawn from CMSAhaNIHAAOS

Definition

Source · Editorial summary grounded in 6 cited references ↓

An HOPD is a clinical setting—either physically on a hospital campus (on-campus) or at a separate location (off-campus)—where outpatient services are furnished under the hospital's provider agreement with Medicare. When a patient is seen at an HOPD, the hospital submits an institutional claim using Type of Bill (TOB) 13X and appends site-specific modifiers. CMS reimburses HOPD services through OPPS, which packages payments into Ambulatory Payment Classifications (APCs) rather than the fee-schedule rates used in freestanding offices. This dual-bill environment means the physician still submits a separate professional-fee claim, but the facility component flows through the hospital.

The financial and regulatory landscape shifted materially after the Balanced Budget Act of 2015 directed CMS to reduce the payment advantage that HOPDs historically enjoyed over freestanding offices. Starting in 2017, newly enrolled off-campus HOPDs began receiving lower, site-neutral payment rates for most services. By 2020, that equalization extended to evaluation and management (E/M) visits at all off-campus HOPDs, eliminating much of the revenue premium that had driven hospital acquisition of physician practices. Existing on-campus HOPDs and grandfathered off-campus sites continue under full OPPS rates for surgical procedures, so the distinction between on-campus and off-campus status remains financially significant.

For orthopedic practices, HOPD status affects everything from how injections and arthroscopic procedures are packaged and paid to which NCCI bundling edits apply at the facility level. Because OPPS uses APC grouping logic rather than individual CPT-level fee schedule rates, several add-on codes and separately billable services in an office setting may be bundled—and therefore not additionally reimbursed—when the same procedure is performed in an HOPD.

Why it matters

Getting the site of service wrong has direct revenue and compliance consequences. If an orthopedic surgeon performs a procedure in an HOPD but the claim is submitted with Place of Service (POS) 11 (office) instead of POS 22 (on-campus outpatient) or POS 19 (off-campus outpatient), Medicare pays the higher non-facility work RVU rate—but that overpayment creates a false-claims exposure when audited. Conversely, failing to recognize that a procedure will be bundled under OPPS APC logic in an HOPD setting (where it might be separately billable in an ASC or office) leads to unexpected reimbursement shortfalls and frustrated revenue-cycle teams. Surgeons who split their time between office, ASC, and HOPD settings must verify site-of-service coding on every claim to protect both collections and compliance.

Common mistakes

Where people most often go wrong with this concept.

Source · Editorial brief grounded in cited references ↓

Using Place of Service 11 (physician office) on the professional claim when the service was actually rendered in an HOPD, inflating the work RVU payment and creating overpayment liability.
Omitting the required PO modifier (off-campus OPPS services) or PN modifier (off-campus physician fee schedule services) on HOPD institutional claims, which can trigger claim rejection or incorrect payment.
Assuming that an injection billable separately in an office setting (e.g., a therapeutic joint injection with imaging guidance) will also be separately reimbursed under OPPS—APC packaging may bundle it.
Treating all HOPDs as equivalent: on-campus and grandfathered off-campus sites still receive full OPPS rates for surgical procedures, while non-grandfathered off-campus sites receive site-neutral rates for E/M visits.
Billing the professional and facility components on the same UB-04 institutional claim; the physician's professional fee must travel on a separate CMS-1500 claim form even when the physician is employed by the hospital.
Expecting NCCI PTP edits to work identically at the HOPD facility level as they do for professional claims—OPPS has its own Outpatient Code Editor (OCE) logic that may bundle differently than physician NCCI edits.

Related codes

Codes commonly involved when this concept appears in practice.

CPT

ICD-10

M17.11 M17.12

Modifiers

26 Professional component 59 Distinct procedural service

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01Why is reimbursement usually higher at an HOPD than at a freestanding office?

HOPDs are paid through OPPS, which historically included a facility fee that covers hospital overhead—nursing, equipment, sterile supply, and administrative costs—on top of the physician's professional fee. Freestanding offices receive only the physician fee schedule rate, which is set lower because CMS assumes overhead is already embedded in the non-facility practice expense RVUs. Site-neutral payment reforms have narrowed this gap for off-campus E/M visits but the differential often persists for surgical procedures at on-campus or grandfathered sites.

02Does my patient pay more out-of-pocket when seen at an HOPD?

Generally yes. Medicare beneficiaries face both a Part B coinsurance (typically 20%) on the OPPS facility payment and a separate coinsurance on the physician's professional fee. In a freestanding office there is only one Part B claim. The higher base payment under OPPS means the 20% coinsurance amount is larger, which can surprise patients who assume all outpatient settings cost the same.

03What is the difference between an on-campus and off-campus HOPD for billing purposes?

An on-campus HOPD is physically located on or contiguous with the main hospital campus as defined by CMS and is paid full OPPS rates. An off-campus HOPD is geographically separate. Off-campus sites enrolled in Medicare before November 2, 2015 are grandfathered and continue to receive OPPS rates for surgical services. Sites enrolled after that date receive site-neutral payment rates (tied to the Medicare Physician Fee Schedule) for most services, with limited exceptions. The billing distinction is captured through Place of Service codes (22 vs. 19) and the PO/PN modifiers.

04Does HOPD status affect which NCCI edits apply?

Yes. The NCCI Procedure-to-Procedure (PTP) edits and Medically Unlikely Edits (MUEs) that apply to physician professional claims are enforced by CMS claims processing contractors. HOPD facility claims processed under OPPS go through the Outpatient Code Editor, which uses related but distinct bundling logic. A code pair that can be unbundled with a modifier on the physician claim may remain bundled in the APC grouper on the facility side, so coders must evaluate both sides of the claim independently.

05Can an orthopedic surgeon employed by a hospital still bill a separate professional fee when operating in the hospital's HOPD?

Yes. Employment by the hospital does not eliminate the professional fee. The surgeon bills the professional component on a CMS-1500 claim with the appropriate Place of Service code, and the hospital separately bills the facility component on a UB-04. The professional claim captures physician work RVUs; the facility claim captures the APC-based facility payment. Both claims must reflect the same date of service and consistent procedure coding.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira AI Scribe

Mira detects when a scheduled procedure or visit is flagged as occurring in a hospital outpatient department and automatically applies the correct Place of Service code (POS 22 for on-campus, POS 19 for off-campus) to the professional claim. For off-campus HOPD encounters, Mira prompts the coder to confirm whether the site is grandfathered under pre-2017 OPPS rules or subject to site-neutral payment, because that distinction changes expected reimbursement benchmarks for the facility component. When orthopedic procedures are performed at an HOPD, Mira cross-references OPPS APC packaging logic to flag add-on codes or imaging-guidance codes that are reimbursable in an office or ASC but bundled under OPPS—preventing write-off surprises. Mira also surfaces the PO or PN modifier requirement for institutional claims and alerts the physician's billing team if the professional claim POS is inconsistent with the facility claim data received from the hospital, reducing dual-claim mismatches before submission.

See Mira's approach

OPPS (Outpatient Prospective Payment System) is the Medicare payment framework under which hospital outpatient department services—including most orthopedic procedures performed in that setting—are reimbursed through pre-determined rates assigned to Ambulatory Payment Classifications (APCs).

APC (Ambulatory Payment Classification) Reimbursement

An Ambulatory Payment Classification (APC) is a Medicare prospective payment grouping used under the Outpatient Prospective Payment System (OPPS) that bundles outpatient hospital services with similar clinical intensity and resource cost into a single, fixed reimbursement rate.

ASC (ambulatory surgical center) Reimbursement

An ambulatory surgical center (ASC) is a Medicare-certified, freestanding or hospital-operated facility that furnishes outpatient surgical services exclusively—meaning patients are treated and discharged the same day without an overnight stay.

NCCI (National Correct Coding Initiative) Coding

The National Correct Coding Initiative (NCCI) is a CMS program of automated prepayment edits that prevent Medicare and Medicaid from paying for procedure code combinations that are incorrectly billed together or billed in quantities that exceed what is clinically reasonable.