Iowa Code § 554.3118: Accrual of cause of action.

1. A cause of action against a maker or an acceptor accrues

a. in the case of a time instrument on the day after maturity;

b. in the case of a demand instrument upon its date or, if no date is stated, on the date of issue.

2. A cause of action against the obligor of a demand or time certificate of deposit accrues upon demand, but demand on a time certificate may not be made until on or after the date of maturity.

3. A cause of action against a drawer of a draft or an endorser of any instrument accrues upon demand following dishonor of the instrument. Notice of dishonor is a demand.

4. Unless an instrument provides otherwise, interest runs at the rate provided by law for a judgment

a. in the case of a maker, acceptor or other primary obligor of a demand instrument, from the date of demand;

b. in all other cases from the date of accrual of the cause of action.