Iowa Income Tax Withholding Payment and Filing Requirements
Employers in Iowa must conform with these state rules relating to filing income tax withholding returns.
Periodic Returns. Quarterly (Form 44-095a) by last day of the month after the end of the quarter; monthly (Form 44-101 and Form 44-095a) by the 15th day of the following month.
Annual Reconciliation Returns. Form VSP (Verified Summary of Annual Payments) due by last day of February.