Yes, the Delaware Division of Revenue requires you file 1099 forms.
Yes, but the 1099-MISC and the 1099-R need to be submitted directly to the Delaware Division of Revenue.
Yes, the state of Delaware mandates the filing of Annual Withholding Reconciliation, Delaware Form W-3 if you are paper filing. Do not submit Federal Form W-3 to Delaware.
Form W-3 is a Transmittal of Wage and Tax Statements used to report the total wages and taxes for all employees.
The filing due dates for Form 1099-MISC (NEC Only) is January 31, 2019 and 1099-MISC (Except NEC) or 1099-R is April 01, 2019.
Delaware supports both paper and electronic filing for 1099 forms, but recommends filing 1099 forms online.
Withholding tax returns filed late are subject to a penalty of 5% per month, plus interest of 0.5% per month from the original due date until paid.