According to the UW General Terms & Conditions (section 28), payment is not considered late if a check, warrant, or electronic transmittal notice has been mailed or issued within the time specified by the contract, or if no terms are specified, within 30 days from the date of receipt of a properly completed invoice, or goods, whichever is later.
Any late payment charges accrued on an invoice will be charged to the fund listed on the purchase order, and subject to buyer review.