When the IRS actually processes your 1099s: the campus completion dates, and what they explain

What a program completion date is

The manual sets, for each return type, "work actions ... and time frames given for the campuses and Enterprise Computing Center-Martinsburg (ECC-MTB) to process IRP documents" (IRM 3.30.123.8, Jan. 1, 2026). A program completion date is the date by which a defined percentage of the processable receipts must have reached the end point: for information returns "Program completion ... will be considered accomplished when the reported output to end point is equal to or greater than 99 percent of the number of processable documents received through the end of the counting period," and for the returns scanned into IRIS "when 99 percent of the current year processable receipts are scanned and sent to the IRIS system" (IRM 3.30.123.8.3.1). The dates are internal targets, not promises to filers, but they are the dates behind every downstream system that reads the returns.

Paper 1099s: August and December

The front end is faster than the completion date suggests. Campuses must "Identify non-scannable/unprocessable documents within three weeks of receipt. During peak processing time, identify within five weeks of receipt," "Mail letters for IRP submissions transmitted by Form 1096 within two weeks of identifying unprocessable documents," and "Perfect and appropriately route and/or process items identified needing research within five weeks of identification" (IRM 3.30.123.8.3). A paper submission with a problem therefore produces a Letter 1865-C within about seven weeks; one without a problem sits in the queue toward the August date. Scanned forms (the 1099-MISC, INT, DIV, K, R and most of the 1098 and 5498 series) go through SCRIPS; the remainder (W-2G, 1099-SA, 1099-LTC, 3921, 3922 and others) are keyed on ISRP. Processing "will begin on January 22, 2026," and August 12 "is the last date GMF transmissions to ECC-MTB can occur" for the first completion (IRM 3.30.123.8.3).

Electronic returns through IRIS and FIRE do not wait for these dates; they post to the Information Returns Master File on their own cycle, which is why the IRPTR guide and the paper guide treat the two routes differently. The Wage and Income transcript the payee sees is built from the same file, and the transcript manual's rule that current-year data is "not available ... until February 17" and may be incomplete "until all payers have filed" (IRM 21.2.3.5.7) is the same lag seen from the other side.

The CP2100 windows

The subsection "pertains to the mailing of tapes" of backup-withholding incorrect-TIN notices, with "ECC-MTB will mail tape notices/listings" and the Detroit computing centre and the Ogden IRS campus handling "paper listings for mailing" (IRM 3.30.123.8.5). The two windows match what payers see: the large autumn mailing covers the returns processed by the first completion date, and the spring mailing picks up late and corrected filings processed by the second. A payer that files on time and gets no CP2100 by the end of October should not assume it is clear until the April run has passed, and a payer that corrected TINs in March should expect those corrections to be reflected only in the autumn run, since "corrections may not be processed at the time the first run is done" (the CP2100 script guide covers that rule). The calendar carries both windows.

Form 945

Form 945 is a tax return rather than an information return, so it is processed on the business-return cycle: "Number of Days in Cycle must normally be 16 days or lower and must not exceed 32, but PCD must be met" (IRM 3.30.123.7.4.5). A 945 with a refund is complete by late February; a balance-due or even 945 by early April. The manual also instructs campuses to suppress the delinquency notice on returns stuck in error status "three weeks prior to the Delinquency Check," which is why a 945 that went to rejects does not usually produce a CP259. The unfiled Form 945 page covers the check itself, which runs sixteen weeks after the due date.

What the dates explain

A payee's blank transcript in March. Paper returns are not complete until August; the transcript shows what has posted. The payee's own copy of the 1099 is the evidence until then.

A CP2100 listing a TIN you fixed. The autumn run uses the file as processed by the first completion date; a correction filed after the original was processed can be on the list. The notice rule is to compare the listing to your records and send no B-Notice where your records already differ.

A levy on a vendor you stopped paying. ACS loads levy sources from the Information Returns Master File each February, "followed by weekly downloads" (IRM 5.19.4.3.5), so the levy reflects last year's completed file.

A late 972CG. Penalty cases are built after the completion dates, which is why a notice for a January filing arrives the following summer or later; the statute page has the three-year clock that the processing lag runs inside.

An extension that was never acknowledged. Paper Forms 8809 are "prioritized, batched, and input into the IRP Home page" and incomplete forms get correspondence "within 15 days of receipt" (IRM 3.30.123.8.3.7); the paper Form 8809 page explains why there is no approval letter.

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