IRIS CSV upload errors and how to fix them
The IRIS Taxpayer Portal reports two kinds of problems: file-level errors that stop the upload, and form-level errors that stop single forms. Most come from a short list of formatting causes.
What the portal shows
When an upload fails, the IRIS Taxpayer Portal shows a red box under "Current Uploaded File" with this line:
"The uploaded file contains one or more errors. Please correct the following and re-upload."
Publication 5717 describes two kinds of message under it:
- File-level errors stop the whole file. Only one shows at a time, so fixing it can reveal the next one. The IRS example is "The file uploaded must be 100KB or less."
- Field-level errors appear together in a table with the row, the column group and a message. The IRS example is row 9, Payer Fields, "Payer ZIP/Postal Code must be exactly 5 or 9 digits."
The tool on this site finds both kinds before you upload, and keeps each file under 250 records and under 100KB.
File rejected at upload
| Cause | Fix |
|---|---|
| Header row differs from the IRS template, or a column was added, removed or moved | Start from a freshly downloaded template for the right form and tax year. Do not rename, reorder or delete columns. |
| More than 250 records | Split the file into parts of 250 or fewer, each with the header row. |
| "The file uploaded must be 100KB or less" | Split into smaller files. Rows with long names and state data can pass 100KB before reaching 250 rows. |
| Blank rows, or a row of only commas under the header | Delete them. The IRS FAQ says templates are sensitive to spaces, commas and blank rows. |
| More than one form type or tax year | Make one file per form type and per tax year. |
| Extra commas or separators beyond the template's columns | Open the CSV in a text editor and remove trailing separators. |
| Not saved as CSV UTF-8 | Save as "CSV UTF-8 (Comma delimited)", or use plain ASCII text. |
Cell formatting errors
| What you see | Why IRIS rejects it | Fix |
|---|---|---|
| 1.045E+05 in an amount | Excel switched to scientific notation | Format the column as Text, or write 104500.00 |
| 7030 as a ZIP code | Excel dropped the leading zero | Use 07030. ZIP codes are 5 or 9 digits with no dash. |
| 123456789 as a TIN | The template wants dashes | SSN, ITIN and ATIN as XXX-XX-XXXX. EIN as XX-XXXXXXX. |
| Double space, or a space at the start or end | Leading, trailing and adjacent spaces are not allowed | Trim spaces and collapse doubles |
| Text on two lines inside one cell | A line break from Alt+Enter | Put the second address line in Address Line 2 |
| Periods or # in names and addresses | Not allowed characters | Write "Apt 5" not "Apt. #5" |
| O'Brien in First or Last Name | Person name fields take letters, spaces and hyphens only | Write OBrien |
| 0.00 in a money column | Zero amounts must be empty | Leave the cell blank |
| Empty 2nd TIN Notice or direct sales box | Check boxes need Y or N | Enter N when it does not apply |
| Dates like 1/5/26 | Two-digit years are not accepted | Use MM/DD/YYYY |
Field length limits
| Field | Maximum | Allowed characters |
|---|---|---|
| Business or entity name line 1 | 40 | Letters, numbers, spaces, - # ( ) & ' |
| Business or entity name line 2 | 40 | Same, plus / and % |
| First, middle, last name, suffix | 20 each | Letters, spaces, hyphens |
| Address line 1 and 2 | 35 each | Letters, numbers, spaces, hyphen, slash |
| City | 40 | Letters and spaces |
| Form account number | 20 | Must not be the TIN |
| State/payer state number | 24 | Letters and digits only |
| Special data entries | 60 | Letters, numbers and common symbols |
The IRS guidelines allow # in business names, but Publication 5717 lists # in names and addresses as a common rejection reason. The tool removes it.
Form-level business rules
- 1099-NEC: Box 1 must have an amount, or Box 2 must be checked.
- 1099-MISC: at least one amount box, or Box 7 checked.
- Name type B needs Business Name Line 1. Name type I needs first and last name.
- State sections: if any State 1 field is filled, State 1 is required, and a selected state needs at least one state amount.
- TIN type is required when a TIN is entered.
Run your file through the IRIS CSV validator to find all of these at once. It fixes the safe ones and lists the rest by row.
Errors that come back after you submit, such as SHAREDIRFORM014 or S1H001, are IRS business rules rather than file formatting. They are explained on the IRIS error codes page.
Edit in a text editor, not Excel
The IRS's own advice: once a CSV is saved, reopening it in Excel and saving again strips the formatting. Leading zeros vanish and long numbers turn into scientific notation. Make small corrections in a text editor such as Notepad, or rerun the file through the tool.
Frequently asked questions
IRIS says my file has errors but does not say where. How do I find them?
I uploaded a CSV and nothing happens when I press Start.
The portal keeps spinning after Add All.
Sources
- IRS Publication 5717, IRIS Taxpayer Portal User Guide (Rev. 9-2026)
- IRS: TY2025 IRIS CSV Template Formatting Guidelines (ZIP)
- IRS: Information Returns Intake System (IRIS) FAQs
- IRS: E-file information returns with IRIS
Last reviewed November 1, 2026.