Establishes 30-day deadline for payment of contracts under the State Procurement Code; sets deadlines for grant payments, contracts, and reimbursement agreements to nonprofits, municipalities, and Alaska Native organizations; requires state agencies to pay interest on late payments; requires prompt notice and explanation to contractors when payment is withheld for unsatisfactory performance or invoicing problems; requires payment of at least 20 percent of a state grant within ten days of the effective date of the grant agreement, and monthly or lump sum payments thereafter; clarifies definition of grants and organizations involved; companion bill to SB 129.