Iowa Admin. Code r. 875-156.3
When awarding a contract for a public improvement to the lowest responsible bidder, the public body shall allow a preference to a resident bidder as against a nonresident bidder that is equal to any preference given or required by the home state or foreign country in which the nonresident bidder is a resident without regard to whether such preferences are actually enforced by the applicable regulatory body in each state. If the bidder is a subsidiary of a parent that would be a nonresident bidder if such parent were to bid on the public improvement in its own name, then the public body shall allow a preference as against such bidder that is equal to the preference given or required by the home state or foreign country of the bidder's parent. In the instance of a labor force preference, a public body shall apply the same resident labor force preference to a public improvement in this state as would be required in the construction of a public improvement by the home state or foreign country of the nonresident bidder, or the parent of a resident bidder if the parent would qualify as a nonresident bidder if such parent were to bid on the public improvement in its own name.
A preference shall not be applied to a subcontractor unless the home state or foreign country of the nonresident bidder to whom the contract was awarded would apply a preference to the subcontractor.
Specific methods of calculating and applying a preference shall mirror those that apply in the home state or foreign country of the nonresident bidder to whom the contract was awarded. In the event that the specific method used by the nonresident bidder's home state or foreign country cannot be determined, the calculation for a labor force preference shall include only the labor force working on the public improvement in Iowa on a regular basis calculated by pay period.
Iowa Admin. Code r. 875-156.3