Iowa Code § 537.3305: No assignment of earnings.

1. A creditor may not take an assignment of earnings of the consumer for payment or as security for payment of a debt arising out of a consumer credit transaction. An assignment of earnings in violation of this section is unenforceable by the assignee of the earnings and revocable by the consumer. This section does not prohibit a consumer from authorizing deductions in favor of a creditor if the authorization is revocable, the consumer is given a complete copy of the writing evidencing the authorization at the time the consumer signs it, and the writing contains on its face a conspicuous notice of the consumer’s right to revoke the authorization.

2. A sale of unpaid earnings made in consideration of the payment of money to or for the account of the seller of the earnings is deemed to be a loan to the seller secured by an assignment of earnings.