CMS-1850-P · Released July 2026 · Comments due August 31, 2026

The answer first: in the Calendar Year 2027 Hospital Outpatient Prospective Payment System (OPPS) and Ambulatory Surgical Center (ASC) Proposed Rule (CMS-1850-P), released July 2026, CMS proposes a 2.4% payment update for both OPPS and ASC rates, built from a 3.2% market basket minus a 0.8 percentage point productivity adjustment. In the same rule, CMS proposes to pay for 340B-acquired drugs at ASP minus 33.4% beginning CY2027, and the proposed 340B rate reaches drugs furnished by nonexcepted off-campus departments. The modest rate lift and the much larger drug-line cut land in the same fee schedule, so a CY2027 outpatient revenue model that stops at "rates went up 2.4%" is wrong. Comments close August 31, 2026.

The rule in five numbers

The update math, exactly as proposed

That equation is the friendly half of the rule. The unfriendly half is the drug line. CMS proposes to move 340B-acquired drug payment to ASP minus 33.4% for CY2027, and the proposal expressly includes drugs furnished by nonexcepted off-campus provider-based departments. For a hospital with meaningful 340B drug volume, the percentage on the drug line dwarfs the percentage on the service line.

Two forces, one net number

The practical consequence: two hospitals with identical outpatient service volume can see opposite CY2027 revenue trajectories depending on their 340B drug mix. An infusion-heavy 340B hospital with off-campus oncology sites carries maximum exposure. A low-drug-volume surgical hospital, or a freestanding ASC, mostly just receives the 2.4%. Your net number is a mix question, and only your own claims data answers it.

The clock

• July 2026 CMS releases CMS-1850-P, the CY2027 OPPS and ASC Proposed Rule, with its fact sheet published at cms.gov/newsroom/fact-sheets.
• August 31, 2026 Comment period closes. Data-backed comments on the 340B proposal and the update factor must be filed by this date.
• CY2027 As proposed, the 2.4% update and the ASP minus 33.4% payment rate for 340B-acquired drugs take effect with the calendar year.

Operator to-do list, in order

1. Pull twelve months of outpatient claims and isolate every line with a 340B-acquired drug. That subset, repriced at ASP minus 33.4%, is your gross exposure to the proposal.
2. Include nonexcepted off-campus department claims in that pull. The proposed rule reaches them, so an exposure model scoped only to on-campus billing understates the cut.
3. Apply the 2.4% update to your OPPS or ASC service-line revenue, then net it against the drug-line reduction. Present one number to finance, the net, not two offsetting percentages.
4. File a comment on CMS-1850-P by August 31, 2026. Comments carrying facility-specific dollar impacts and access implications are the ones worth CMS staff time. Generic objections are not.
5. Reforecast CY2027 budgets and any payer contracts with escalators or carve-outs referenced to Medicare outpatient rates, since a finalized rule moves those baselines too.
6. Brief service-line leaders in infusion, oncology and specialty pharmacy now. If the proposal finalizes as written, their CY2027 margin story changes and they should not learn it from the remit.

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