Internal Revenue Service Where’s My Refund? Federal Employee’s Withholding Certificate (Form W-4) Request for Taxpayer Identification Number and Certification (Form W-9) Tax Withholding Estimator Minnesota Department of Revenue Where’s My Refund? Income Tax Credits Business Registration Minnesota Employee Withholding (Form W-4MN) Wisconsin Department of Revenue Where’s My Refund? Tax Incentives for Businesses Business Registration Wisconsin Employee Withholding Agreement (Form WT-4A)
