In the current day phenomena of globalization, to face the win-win situation between two parties, there should be an understanding with some coordination mechanisms. In most of the recent literature, the widely used approach in supply chain collaboration is credit period. This paper describes about the nonlinear price dependent demand under credit period in a two-echelon inventory system. Single product is shipped from single manufacturer (producer) to the single retailer (vendor), where the manufacturer provides credit period to the retailer. In these criteria, the total supply chain is evaluated in terms of cycle time, retailers' replenishment quantity, number of deliveries and the total relevant cost. To solve optimality conditions, MATLAB program is written in computer. To see variations in optimality of decision variables, sensitivity analysis is carried out with a numerical illustration. Finally, we present results, some of them are validations, which prove, that our new approach is reliable with nonlinear phenomena. This study aims to applying credit period scenario to the retailer with nonlinear price dependent demand. With this model, some of the managerial decision like cycle time, retailers' replenishment quantity, number of deliveries and the yearly overall supply chain cost are obtained. © 2017 Elsevier Ltd. All rights reserved.