Section 1475.1 - When commissions become due(a) Contract.--The terms of the contract, whether or not in writing, between the principal and sales representative shall determine when commissions become due.(b) Custom and usage.--If the time when commissions become due cannot be determined by a contract between the principal and sales representative, the past practices of the parties shall control, or, if there are no past practices, the custom and usage prevalent in this Commonwealth for the business that is the subject of the relationship between the parties shall control.1988, Dec. 21, P.L. 1881, No. 184, § 5.1, added 1998, Dec. 21, P.L. 1305, No. 173, §3, effective 1/1/1999.