Iowa is not a traditional open carry state, but no permit is required to open carry except when in vehicles or when inside city limits. Open carry in cities is technically legal with an Iowa permit to carry weapons, however Iowa is a may-issue state, and some sheriffs have indicated that they will revoke your permit for open carrying.
Complete State Preemption of All Firearm Laws
Iowa honors Minnesota permit.
Chapter 724 of the Iowa Code and Administrative Rules, 661, Chapter 91 contain information on Iowa’s weapon laws and the issuance of weapon permits in Iowa.
Does this mean you may OC on out of state permit? I am 99.9% sure, but have not confirmed 100% so far. Need to connect the dots between CC and OC. Let's wait and see if someone provides more direct information with a link.