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Bulk Filer Requirement: Effective April 7, 2008, accountants or tax filing services who file withholding tax returns and payments on behalf of employers must register with the Department as a bulk filer and must utilize their bulk filer registration when filing withholding tax returns on behalf of their clients.
Apply To Become A Bulk Filer: Form BF-1: Application to Become a Bulk Filer (Updated: 05/02/2016)
Selecting a File Type for Bulk Filing: A-3 Bulk Filing File Type
Describing the Fields in Your File using the File Layout Screen
Creating and Extracting W-2 Import File
Checking Files For Errors
Using Excel Spreadsheet to Upload Files