Iowa Code § 504.501: Registered office and registered agent.

A corporation shall continuously maintain both of the following in this state:

1. A registered office with the same address as that of the registered agent.

2. A registered agent, who may be any of the following:

a. An individual who resides in this state and whose business office is identical with the registered office.

b. A domestic business corporation, domestic limited liability company, or domestic nonprofit corporation whose business office is identical to the registered office.

c. A foreign business corporation, foreign limited liability company, or foreign nonprofit corporation authorized to transact business in this state whose business office is identical to the registered office.