Please see the below for instructions on where to mail your Iowa Income tax return:
Individual Income Tax Forms
If you file on paper, send your return to:Iowa Income Tax Document Processing
PO Box 9187
Des Moines, IA 50306-9187
If tax is due with your return, include a check or money order and an IA 1040V Payment Voucher.
https://tax.iowa.gov/mailing-addresses