Iowa Code § 542B.18
Certificates of licensure shall expire in intervals as determined by the board. Renewal may be effected by the payment of a fee the amount of which shall be determined by the board. The failure on the part of any licensee to renew a certificate in the month of expiration as required above shall not deprive a person of the right of renewal. A person who fails to renew a certificate by the expiration date shall be allowed to do so within thirty days following its expiration, but the board may assess a reasonable penalty. For the duration of any war in which the United States is engaged the board may, in its discretion, defer the collection of renewal fees without penalty, which have or may become due from licensed professional engineers who are employed in the war effort, and residing outside the state, or who are members of the armed forces of the United States, and may renew the engineering certificates of licensed professional engineers.
Iowa Code § 542B.18
96 Acts, ch 1055, §5, 6, 8; 2012 Acts, ch 1009, § 18