The facility claim is its own claim
When a procedure is performed in an ambulatory surgery center, the surgeon, the anesthesia provider and the ASC each bill separately. The ASC’s facility claim follows different rules from the professional claims: it is paid from a facility fee schedule, uses its own payment indicators, and is affected by contract terms that professional billers rarely see. Coding the facility claim from the operative report with the same care as the surgeon’s claim — and making sure the two agree — prevents many ASC denials.
Claim format depends on the payer
Medicare ASCs bill their Medicare Administrative Contractor on the professional claim format (the 837P electronic claim or the paper CMS-1500), not the institutional format hospitals use. Many Medicaid programs and commercial plans follow the same approach, but some require the institutional format (837I or UB-04) with revenue codes. The required format is part of each payer’s setup, and sending the wrong one leads to rejections.
Medicare ASC rules that shape payment
- Covered procedures list: Medicare pays an ASC only for procedures on its ASC covered procedures list, updated each year with the hospital outpatient and ASC payment rule. Scheduling should check it before the case is booked.
- Multiple-procedure discounting: when several procedures subject to discounting are performed together, the highest-paying procedure is paid in full and the others at a reduced rate. Line order and payment indicators matter.
- Discontinued procedures: modifier 73 applies when a procedure is stopped after preparation but before anesthesia, and modifier 74 when it is stopped after anesthesia has started. They are paid differently, so the timing must be documented.
- Packaged and separately paid items: many supplies, drugs and ancillary services are packaged into the facility payment; certain devices, drugs and biologicals are paid separately when Medicare designates them as such.
- Device-intensive procedures: procedures with high device costs are paid on a different basis, and the device must be reported correctly on the claim.
Commercial contracts and implants
Commercial ASC contracts vary widely. Many pay a case rate or a percentage of a fee schedule and then carve out implants, high-cost drugs or specific procedures for separate payment — sometimes at invoice cost plus a percentage. Those carve-outs are only paid if the claim reports them the way the contract requires and the invoice is attached or available when requested. Payments are checked against the contract on every remittance, because carve-outs are where underpayments are most often missed. Many commercial plans also require authorization for the facility as well as the surgeon — see prior authorization services.