IRIS CSV limit: 250 records per file
One CSV file can hold at most 250 forms, not counting the header row. You then submit at most 100 forms at a time.
Two different limits are easy to mix up:
| Limit | Number | Where it says so |
|---|---|---|
| Records in one CSV file | 250 | Publication 5717 (Rev. 9-2026), section 3.5: "The file can only contain a maximum of 250 records." |
| Forms in one submission | 100 | Publication 5717, section 3.6.1: "There is a maximum number of 100 forms per submission." |
| Forms in one download | 100 | Publication 5717, section 3.6.1 |
| Tax years and form types in one file | 1 of each | Publication 5717, section 3.5 |
The per-file limit used to be 100. IRS working group notes from 14 May 2025 list the change from 100 to 250, and the IRS answered in February 2025 that you may upload an unlimited number of files. Older pages still quote 100.
Perfrow cuts a long list into files of at most 250 on your template's header row and writes a checklist with one line per file and per submission.
Fix the whole file at once
Drop in your blank IRIS template and your spreadsheet. Perfrow cleans every row, tells you which ones need you, and writes CSVs of at most 250 records. It runs in your browser, so names and TINs stay on your computer.
Open the 1099-NEC CSV fixerQuestions
- How many records can an IRIS CSV file have?
- At most 250, header row not included, per Publication 5717 (Rev. 9-2026).
- Is the IRIS limit 100 or 250?
- 250 records per CSV file. 100 is the most forms you can submit, or download, at one time.
- Can I upload more than one CSV file?
- Yes. In its February 2025 working group answers the IRS said you may submit an unlimited number of CSV files.
Other answers: All 54 columns · Required fields · Character limits · State codes · Why files get rejected · Scientific notation · ZIP code format · Date format · Line breaks · Extra spaces · Periods and # · $0.00 cells · Y/N check boxes · Tax year · Error types · Headers do not match · From QuickBooks · TIN format · Key dates