WithfileConvert a 1042-S file for IRIS
Everything happens in this browser tab. Nothing is uploaded: once the page has loaded you can switch off your network and it still works.
1. Your files
Publication 1187 files (.txt, .dat or no extension) made for FIRE, or spreadsheets in the IRIS Form 1042-S layout (CSV or XLSX). Several files at once are fine.
or choose them from your computer
Add the blank 1042-S CSV template you downloaded from the IRIS portal and Withfile copies its exact header row.
2. Result
IRIS Taxpayer Portal CSV files (Form 1042-S)
Control totals
Each withholding agent's reconciliation "C" record compared with the sum of its recipient "Q" records.
| Withholding agent | Check | Year | C record | Sum of Q records | Match |
|---|
Issues and fixes
Errors keep a form out of the CSVs. "Review" forms are in the CSVs but deserve a look. TINs are masked on screen.
| Type | Record | Withholding agent | Recipient | Field | What happened | Before → after |
|---|
License
Checking is free. Downloading CSVs built from your own data needs a license: Agent $790 (1 withholding agent EIN), Group $1,490 (10), Firm $2,900 (unlimited). Founding offer: $474, $894 or $1,740 with FOUNDING40 until 30 Nov, applied automatically at checkout.
Have a license key?
Keep a copy of your key: paste it on any computer your team uses. Lost it? Reply to your Paddle receipt and we resend it.