Surgery center vs hospital outpatient: the price split
For cataract surgery with a lens (CPT 66984), Medicare's 2026 facility payment is $1,255.73 to an ambulatory surgery center and $2,357.81 to a hospital outpatient department, and the surgeon's payment is the same in both; the other five codes below follow the same pattern. The gap sits in one layer. It is a Medicare comparison, not a prediction of any patient's price, and it only works layer by layer.
The six codes, side by side
| Procedure (CPT) | Hospital outpatient facility payment (APC) | Surgery center facility payment | Hospital minus surgery center | Patient share: hospital minimum copay | Patient share: surgery center, 20% |
|---|---|---|---|---|---|
| Cataract removal with lens insertion, no endoscopic cyclophotocoagulation (66984) | $2,357.81 (APC 5491) | $1,255.73 | $1,102.08 | $471.57 | $251.15 |
| Knee arthroscopy with meniscectomy, medial and lateral (29881) | $3,342.87 (APC 5113) | $1,644.87 | $1,698.00 | $668.58 | $328.97 |
| Carpal tunnel release (64721) | $1,995.02 (APC 5431) | $948.66 | $1,046.36 | $399.01 | $189.73 |
| Diagnostic colonoscopy (45378) | $950.10 (APC 5311) | $510.49 | $439.61 | $190.02 | $102.10 |
| Colonoscopy with biopsy (45380) | $1,222.56 (APC 5312) | $656.75 | $565.81 | $244.52 | $131.35 |
| Upper endoscopy, diagnostic (43235) | $926.63 (APC 5301) | $497.85 | $428.78 | $185.33 | $99.57 |
The hospital figures are the national unadjusted rates in the CMS OPPS October 2026 Addendum B, updated October 14, 2026. The surgery center figures are the payment rates in the CMS October 2026 ASC Addendum AA. Both are for calendar year 2026, read October 23, 2026. Every code shows payment indicator A2 in the ASC list, which CMS defines as a surgical procedure on the ASC list in 2007 with payment based on the OPPS relative payment weight. The patient columns assume the Part B deductible has already been met. Wage-index adjustment for the hospital, and the geographic adjustment that applies in some places, are not applied here.
The three endoscopy codes show the same relationship between the two payment scales, and the orthopedic and nerve codes show a wider gap in dollars. That pattern is a sign the gap is built into the two payment formulas rather than any single code.
Why the gap exists: two weights, two conversion factors
Both systems pay a relative weight times a dollar conversion factor. The addenda print the weights and the payments, so the factors can be recovered by division. For the cataract code the hospital weight is 25.7924 and the payment is $2,357.81, which is about $91.41 per weight unit. The ASC weight is 22.2955 and the payment is $1,255.73, about $56.32 per unit. The same two factors reproduce the other codes in the table to the cent. So the surgery center's dollar per weight unit is $56.32 against $91.41, and for these codes the ASC weight is also lower than the hospital weight, which compounds the difference.
| Code | Hospital weight | ASC weight | Weight difference |
|---|---|---|---|
| 66984 | 25.7924 | 22.2955 | 3.4969 lower |
| 29881 | 36.5681 | 29.2047 | 7.3634 lower |
| 64721 | 21.8238 | 16.8435 | 4.9803 lower |
| 45378, 45380, 43235 | 10.3933, 13.3737, 10.1365 | 9.0638, 11.6607, 8.8393 | 1.3295, 1.7130 and 1.2972 lower |
The conversion factors are derived here by dividing published payments by published weights, and CMS does not label them this way in the addenda. What the arithmetic says is only that Medicare pays the two settings through two separate rate scales. Nothing in it says that a commercial plan or a facility's cash price follows the same ratio, and this page does not claim that they do.
The layer that does not move: the surgeon
The CMS physician fee schedule documentation says facility practice expense values are used for services performed in inpatient or outpatient hospital settings, emergency rooms, skilled nursing facilities or ambulatory surgical centers, and non-facility values for all other settings. A surgeon operating in a hospital outpatient department and a surgeon operating in a surgery center both bill the facility rate. The surgeon's own price is therefore not a reason to prefer either setting.
| Code | Surgeon, facility rate (Michigan Locality 01) | 20% share | Non-facility rate, where one exists |
|---|---|---|---|
| 66984 | $467.80 | $93.56 | Not priced for the office |
| 29881 | $539.38 | $107.88 | Not priced for the office |
| 64721 | $437.89 | $87.58 | $495.26 |
| 45378 | $172.49 | $34.50 | $378.46 |
| 45380 | $185.64 | $37.13 | $477.34 |
| 43235 | $114.85 | $22.97 | $319.52 |
These are Medicare physician fee schedule amounts for Michigan Locality 01 (Detroit) from the CMS October 2026 release; another locality moves them modestly. Where the file shows a non-facility amount, it applies to a procedure performed in an office, which is a third setting with its own pricing and not a variant of the two compared here. The non-facility amounts for the endoscopy codes are more than double the facility amounts, because the office rate includes the equipment and staff that a facility bills for separately. A patient is rarely offered that choice for these codes, so treat the column as context for a quote, not as an option.
Anesthesia is a third bill in either setting
Whatever the facility, the anesthesia provider bills separately, under the same formula: base units plus time units, times the locality conversion factor. The base units come from the CMS file, and the Detroit factor for 2026 is $21.32. The times below are invented to show scale.
| Procedure | Anesthesia code | Base units | Invented time | Medicare anchor |
|---|---|---|---|---|
| Cataract surgery | 00142 | 4 | 20 minutes (1.3 units) | (4 + 1.3) x $21.32 = $113.00 |
| Knee arthroscopy | 01400 | 4 | 60 minutes (4 units) | (4 + 4) x $21.32 = $170.56 |
| Carpal tunnel release | 01810 | 3 | 30 minutes (2 units) | (3 + 2) x $21.32 = $106.60 |
| Diagnostic colonoscopy | 00811 | 4 | 30 minutes (2 units) | (4 + 2) x $21.32 = $127.92 |
| Upper endoscopy | 00731 | 5 | 20 minutes (1.3 units) | (5 + 1.3) x $21.32 = $134.32 |
Anesthesia is not part of the facility payment in either system, and whether it is part of a quote depends on who writes the quote. The anesthesia guide explains the formula and the questions to ask. The point for this comparison is that the third layer is the same arithmetic in both settings, so a quote that includes it at one facility and omits it at the other is not comparable until it is added.
What a Medicare patient owes in each setting
Medicare.gov states that after the Part B deductible you pay 20 percent of the Medicare-approved amount to both the ambulatory surgical center and the doctors who treat you, and that you pay all facility fees for non-covered procedures. In the hospital outpatient setting, the patient share of the facility payment is the copayment shown in the OPPS addendum, which for these codes works out to 20 percent of the national payment. The 2026 Part B deductible is $283.
Take the cataract code, assuming the deductible has been met: the facility share is $471.57 at the hospital and $251.15 at the surgery center, a difference of $220.42, and the surgeon's 20 percent share is $93.56 in both. For the knee code the facility difference is $339.61 and the surgeon's share is $107.88 in both. In each case the setting changes one line and leaves the other alone. A patient with a Medicare Savings Programs QMB status owes none of these Medicare cost-sharing amounts, as the Medicare Savings Programs guide explains, and a patient with a Medigap plan should read the plan's rules for outpatient coinsurance in writing.
Larger operations, where the patient-share ordering can flip
The ASC list has grown well beyond cataracts and scopes, and the larger codes show a feature the small ones hide. The OPPS addendum caps the beneficiary copayment on some hospital outpatient procedures at the Part A inpatient deductible, $1,736 for 2026. The ASC addendum states a flat rule instead: Medicare pays 80 percent of the total payment amount and the beneficiary coinsurance is 20 percent of it, with no cap printed. When a procedure's 20 percent is bigger than the cap, the ordering of the patient's share reverses even though the setting with the lower facility payment is still the ASC.
| Procedure (CPT) | Hospital outpatient payment | Hospital patient share | Surgery center payment | Surgery center 20% |
|---|---|---|---|---|
| Total knee arthroplasty (27447) | $13,116.76 (APC 5115) | $1,736.00, capped at the inpatient deductible (20% would be $2,623.36) | $9,393.16 | $1,878.63 |
| Total hip arthroplasty (27130) | $13,116.76 (APC 5115) | $1,736.00, capped (20% would be $2,623.36) | $9,614.11 | $1,922.82 |
| Laparoscopic cholecystectomy (47562) | $6,176.47 (APC 5361) | $1,235.30 | $3,030.97 | $606.19 |
| Laparoscopic appendectomy (44970) | $6,176.47 (APC 5361) | $1,235.30 | $3,030.97 | $606.19 |
| Partial mastectomy (19301) | $4,000.24 (APC 5091) | $800.05 | $1,603.18 | $320.64 |
For the two joint replacements, the surgery center's facility payment is $9,393.16 and $9,614.11 against $13,116.76, a much narrower gap in dollars than for the six codes above, and the patient's 20 percent exceeds the hospital copayment cap by $142.63 for the knee and $186.82 for the hip. These are billing outcomes of how two published rules interact, not advice about where to have anything done, and the surgeon's fee is the same in both settings: $1,237.92 for the knee code and $1,241.22 for the hip code in Michigan Locality 01. CMS marks both joint codes with payment indicator J8, device-intensive procedure paid at an adjusted rate, so more of each payment is the device itself. Whether a given patient's copayment is capped can depend on supplemental coverage and on rules in the full regulation, so ask the facility for the patient-share figure in writing instead of calculating it from this table.
What the surgery center payment packages and excludes
Two more addenda explain what a facility payment contains. Addendum BB lists ancillary items integral to covered procedures, and many implantable items there carry payment indicator N1, which CMS defines as packaged service or item with no separate payment made. The anchor/screw (C1713), implantable joint device (C1776), implantable mesh (C1781), human tissue graft (C1762) and prosthetic implant (L8699) entries are examples. For Medicare, the implant is inside the facility payment. For anyone else, whether the implant is inside the quote is exactly the fifth question below, and it can be the largest line in an orthopedic procedure.
Addendum EE is the other boundary. It lists the surgical procedures excluded from payment in ASCs for 2026, more than 1,500 entries in the October file, among them laparoscopic sleeve gastrectomy (43775) and total hysterectomy (58150). A procedure on that list is not paid as an ASC procedure at all, so a quote from a surgery center for one of those codes would be for something other than a Medicare-style ASC service. If a facility is quoting a code that appears on neither addendum, ask which payment system it assumes.
When the building name misleads
The most useful distinction in this whole comparison is not between a hospital and a surgery center. It is between two billing identities. CMS's place-of-service code set defines code 19 as an off-campus outpatient hospital, a portion of an off-campus hospital provider-based department that provides diagnostic, therapeutic, surgical, nonsurgical and rehabilitation services to patients who do not require hospitalization. It defines code 22 as the on-campus equivalent, and code 24 as an ambulatory surgical center, a freestanding facility, other than a physician's office, where surgical and diagnostic services are provided on an ambulatory basis. A surgical suite across town can be code 19, billed as part of a hospital with the hospital's payment system, or code 24, billed as a surgery center, with no visible difference from the street.
This is why the question to ask is not "are you a hospital?" Ask the billing office these instead:
- Will this facility bill my procedure as a hospital outpatient department or as an ambulatory surgical center? What place-of-service code will be on the claim?
- Does the surgeon bill separately, and who is the anesthesia provider and what do they charge?
- Is a pathology or radiology charge expected? Who bills it?
- Does your price assume one procedure code? What changes if a second is added during the same session?
- Does the price include implants, supplies and drugs, or are they listed separately?
- Can I have the price per layer, with the code, in writing?
The cataract rows of the addendum show why the fifth question is not a throwaway. In the ASC device offset table (Addendum FF), CMS lists the device portion of the cataract code's ASC payment: about 9.26 percent of the ASC payment for 66984, or $116.28. Implant-heavy codes carry more of their payment in the device, and a quote that excludes the lens or the hardware can look far lower than one that includes it. That is a quoting issue, not a Medicare rule, but the table shows how large the item can be.
Code by code: what a neighboring code changes
A quote is for a code, and a code one step away can move one layer and leave the others alone. The CMS files show which layer moves for four neighboring pairs.
| Pair | Hospital facility payment | Surgery center payment | Surgeon, facility rate |
|---|---|---|---|
| Cataract 66984 and the complex version 66982 | Both $2,357.81 | Both $1,255.73 | $467.80 and $639.24, a difference of $171.44 |
| Knee arthroscopy 29881 and 29880 | Both $3,342.87 | Both $1,644.87 | $539.38 and $558.25, a difference of $18.87 |
| Colonoscopy 45378 and the version with biopsy 45380 | $950.10 and $1,222.56, a difference of $272.46 | $510.49 and $656.75, a difference of $146.26 | $172.49 and $185.64, a difference of $13.15 |
| Upper endoscopy 43235 and the version with biopsy 43239 | Both $926.63 | Both $497.85 | $114.85 and $128.48, a difference of $13.63 |
The cataract pair is the clearest. The facility payment is identical in both settings whichever code is billed, so a patient whose procedure is coded as the complex version sees the whole change in the surgeon's line. For colonoscopy the reverse is true: adding a biopsy moves the facility payment by $272.46 at the hospital and $146.26 at the surgery center, but the surgeon's line barely changes. For the upper endoscopy pair the biopsy changes only the surgeon's line, by $13.63. A quote that was built for the plainer code is therefore not safe to assume for the one with the add-on, and the question to ask is the fourth one in the list below: what changes if the second code is added.
When a biopsy is taken, a separate pathology bill can follow from a different group. For scale, the CMS physician fee schedule anchor for a standard tissue examination by a pathologist (CPT 88305) is $69.02 in Michigan Locality 01, and the hospital outpatient addendum lists the same code at $53.24 under APC 5671 for a facility that bills it. Neither is included in the colonoscopy or endoscopy rows above. The pathology group is a fourth billing party, with its own network status, which is why a quote for the facility, the surgeon and the anesthesia provider can still leave one bill out.
Normalizing two quotes: an invented cataract example
The reason to build the layer table is that quotes rarely arrive in matching shapes. Suppose a patient who is not using Medicare asks two facilities for a price for cataract surgery with lens insertion, CPT 66984, and gets these answers. The figures are invented.
| Layer | Surgery center quote | Hospital outpatient quote |
|---|---|---|
| Facility | "$2,400 facility fee" | "$3,100 all-inclusive" |
| Surgeon | Not mentioned | Included |
| Anesthesia | Not mentioned | Included |
| Standard lens | Included | Included |
| Upgraded lens | Not mentioned | Not mentioned |
| Place-of-service code | 24, surgery center | 22, hospital outpatient |
Compared as written, the surgery center looks $700 cheaper. Compared by layer, the comparison is not yet possible: the surgery center's figure leaves out the surgeon and the anesthesia provider, and the hospital's figure includes both. The next step is not to subtract. It is to go back to the surgery center with the same two questions the hospital already answered and ask for the surgeon's and the anesthesia provider's prices, in writing, with their codes. If the surgeon's fee is $600 and the anesthesia charge is $300, the surgery center's total is $3,300, and it is the more expensive of the two by $200. If they are smaller, the surgery center may stay ahead. The point is that the comparison can only be settled once both columns are complete.
The Medicare anchors are useful for exactly this check. The surgeon's facility-rate anchor for 66984 is $467.80 in Michigan Locality 01 and the anesthesia anchor in the example above is $113.00 on an invented time, so a surgeon's fee or anesthesia charge in the same range as those anchors is unremarkable, and one many times larger is a line to ask about. The anchors do not say what is right. They say what scale the layer lives on.
What does not carry over to other payers
Everything above is Medicare. Four limits apply to anyone who is not on Medicare.
- Commercial payers negotiate their own rates in each setting, and neither the ratio nor the order is guaranteed to match Medicare's.
- Self-pay prices are set by each facility. No verified self-pay range exists for these codes, so none is shown.
- The sum of the layers is not published. Facility, surgeon and anesthesia come from three different payment systems and three different bills. This page shows them side by side, not added up.
- Network status is a separate question. A surgery center, a surgeon and an anesthesia group can each be in or out of a plan's network independently, so the same plan can treat the three layers differently. The estimate guide shows how to ask the convening provider to account for all three.
A scheduled procedure is the kind of care the Good Faith Estimate rules were written for, so a patient who is uninsured or not using insurance can ask each facility for one; the deadlines and the dispute process are in the estimate guide. The six questions above are what make an estimate complete, and the final step is to confirm your price in writing before service, with the facility, the surgeon and the anesthesia provider each named.
A comparison sheet to fill in
| Layer | Hospital outpatient department | Surgery center |
|---|---|---|
| Facility price and what it includes | ||
| Billing identity and place-of-service code | ||
| Surgeon price (the same group in both?) | ||
| Anesthesia group, code and price | ||
| Pathology or radiology, if expected | ||
| Implants, supplies and drugs | ||
| What changes if a second procedure is added | ||
| Date, name and written confirmation |
Fill in one column per facility and compare layer by layer. A blank cell is the answer to which quote is incomplete. The structure of this table is the same one that the imaging settings guide uses for scans, and for procedures with a cash price, the cash price guide has the wording for the call. To price one of the six codes on its own, start from its page: cataract surgery, knee arthroscopy or colonoscopy.
FAQ: surgery center and hospital outpatient billing
What do the payment indicators A2, G2 and J8 mean on the ASC list?
G2 means a non-office-based surgical procedure added to the ASC list in 2008 or later, with payment based on the OPPS weight, and J8 means a device-intensive procedure paid at an adjusted rate. The laparoscopic abdominal operations in the larger-operations table are G2 and the two joint replacements are J8. N1, which appears on implant lines in the ancillary addendum, means the item is packaged and no separate payment is made.
Can some surgical codes be office-based on the ASC list?
Yes. CMS marks some procedures P2, P3 or R2, meaning office-based surgical procedures added to the ASC list in 2008 or later, with payment based on either the OPPS weight or the physician fee schedule non-facility practice expense. The designation reflects a comparison of rates and is temporary for codes marked with an asterisk. For those codes, the office is a third setting with its own price.
How often does CMS update the ASC rates?
Quarterly. The CMS addenda page lists ASC files for January, April, July and October of 2026, among others, so the October 2026 figures used here are the latest of the year and may be revised in January. Because the rates are weights times a conversion factor, a quote that was priced from an older quarter may differ slightly from these numbers.
What does the 090 global period on the surgeon's code cover?
In CMS's fee schedule documentation, 090 means major surgery with a one-day preoperative period and a 90-day postoperative period included in the fee schedule amount, while 000 marks endoscopic or minor procedures with related values on the day of the procedure only. The cataract, knee and carpal tunnel codes carry 090; the colonoscopy and endoscopy codes carry 000. The surgeon's amount in this page's tables is therefore not a per-visit fee.
Do I pay for facility fees if Medicare does not cover the procedure?
Yes. Medicare.gov says that in addition to the 20 percent for covered services, you pay all facility fees for non-covered procedures you get in an ambulatory surgical center. A procedure on the exclusion list in Addendum EE, or one Medicare does not cover for you, is outside the payment tables on this page, and the facility sets its own charge for it.
Addenda and files used
CMS, ASC Payment Rates and Addenda, October 2026 ASC approved HCPCS code payment rates (Addendum AA, DD1 and FF), https://www.cms.gov/files/zip/october-2026-asc-approved-hcpcs-code-payment-rates.zip, read October 23, 2026. CMS, OPPS October 2026 Addendum B (updated October 14, 2026), https://www.cms.gov/files/zip/October-2026-OPPS-Addendum-B.zip, read October 23, 2026. CMS, Physician Fee Schedule relative value files RVU26D (October 2026 release) and its documentation, amounts computed for Michigan Locality 01, read October 23, 2026. CMS, 2026 anesthesia conversion factors and base units, read October 23, 2026. CMS, Place of Service Code Set (page last modified February 17, 2026), https://www.cms.gov/medicare/coding-billing/place-of-service-codes/code-sets, read October 23, 2026. Medicare.gov, Ambulatory surgical centers, https://www.medicare.gov/coverage/ambulatory-surgical-centers, read October 23, 2026. CMS, Know your rights when not using insurance, read October 23, 2026. Conversion factors and ratios in this page are derived by division from the published addenda. Medicare amounts are payment rates, not patient prices.