Downcoded
October 2, 20263 min readFree

Why Two Medicare Files Disagree About Which Codes Are Dead

The October ASC addenda went up at 4:49pm Thursday, after the rates in them took effect and almost eight hours behind the hospital outpatient file. The two releases came out of the same quarterly update and they disagree about 19 codes: the ASC file keeps 12 that CMS deleted from the OPPS file and deletes 7 the OPPS file kept. The change request that is supposed to describe the ASC file has not issued.

CMS deleted HCPCS code C8010 on October 1 and put it in writing. Its October outpatient transmittal gives the code status indicator D and an APC of N/A, and says a new Category III code took over the procedure.

On October 1, at 4:49 in the afternoon, CMS posted the October ASC addenda. Open Addendum FF in that zip and C8010 has an APC, a 31% device offset and an October OPPS payment rate of $12,500.50.

One stray row. The habit it belongs to runs through the whole release.

"Which of your two October files is telling you the truth about a dead code?"

Nothing Moved on the Surgical Side

Addendum AA carries the ASC covered surgical procedures, 4,847 of them in October against 4,833 in July. Of the 4,334 codes priced in both quarters, 4,331 are identical to the cent.

The three that differ differ by rounding. July published 0870T at 23824.947731066895; October publishes 23824.95.

Same with 0871T and 0872T.

So the October surgical rates contain no rate change at all. Worth knowing before you spend an afternoon reconciling them.

The same artifact is sitting inside the drug addendum, where it matters more. Addendum BB shows 556 changed rates against July, and 57 of those are the rounding again, which leaves 499 real reprices plus thirteen codes that gained or lost a price outright.

One surgical line did change, and it is C8010: $8,509.13 in July, nothing in October.

The Same 19 Codes, Two Different Answers

Eighteen codes dropped out of the October OPPS Addendum B, and the ASC release handles them the opposite way:

  • Twelve of the eighteen are still in the October ASC book, eleven of them stamped with payment indicator D5, which Addendum DD1 defines as "deleted/discontinued code; no payment made." The D5 count in the July ASC release was zero. CMS started using the indicator this quarter.
  • Eight codes newly carry OPPS status indicator E1 in October, all eight having been K in July. Seven of those eight were in the ASC book, and the October ASC release deletes all seven outright.

Twelve one way, seven the other, same quarterly update, two files posted seven hours and fifty minutes apart on the same Thursday. Ten of the nineteen were separately payable in July, running from $8,509.13 down to $0.84 (chart below).

Every one of the ten pays nothing in October. The two files just disagree about how to say so, and the disagreement is systematic: the codes the ASC file keeps and marks dead are exactly the codes OPPS dropped, and the codes the ASC file drops are exactly the codes OPPS kept.

If your quarterly routine is to diff Addendum B and push the result at your ASC schedule, you get both halves wrong.

The twelve look alive because nothing told you they died. The seven look dead because E1 reads like a deletion when it is a code CMS is still printing.

There Is No Change Request to Read

The CMS page hosting these files says it plainly: "Files described in the ASC quarterly change request transmittals are accessible below." July's was R13836CP, issued June 24, a week ahead of the quarter it governed.

There is no October 2026 ASC change request. The transmittal index tops out at R13981MSP, issued this morning, and nothing on it is an ASC payment update.

The OPPS side got R13978CP on September 29, which is where the C8010 deletion is spelled out. The ASC side got a zip file.

The zip also changed shape. July shipped an xlsx plus a folder of six comma-delimited CSVs; October ships the xlsx plus six tab-delimited .txt files with the rate columns formatted as dollar strings.

Anything you built to read last quarter's release reads nothing this quarter.

Final Thoughts

Late ASC files are not new. July's landed on the 13th, twelve days into its own quarter.

What the October release shows is what happens when a file arrives without the document that explains it. The OPPS transmittal tells you in a labelled section that 1091T replaces C8010 and that C8010 has no APC.

The ASC file, with no transmittal behind it, assigns C8010 an APC anyway, prices it at $12,500.50, and prices its replacement at $11,912.65 somewhere else in the same zip.

None of that changes a single October payment. It does tell you which of your two quarterly reconciliations is running on evidence and which one is running on an assumption that the files agree.

Thanks for reading.