With the growing importance of sustainability for firms to gain a competitive advantage, an increasing number of companies have adopted various mechanisms to achieve their sustainability goals. Some firms have begun to adopt financing mechanisms to encourage the sustainability practice of their suppliers and to improve their supply chain efficiency with a different payment term. We consider two financing mechanisms based on practice, namely, the retailer's advanced payment (AP) model in which the downstream retailer makes an early payment to the upstream supplier within a certain payment term, and the reverse factoring (RF) model in which the downstream retailer cooperates with and encourages a bank to offer a loan to the upstream supplier. To illustrate how these mechanisms improve sustainable development and supply chain efficiency, we develop a model that explicitly captures the impact of payment on the sustainability efforts of suppliers in a supply chain and explores the conditions under which each financing mechanism benefits the players. We describe the equilibrium strategies between the supplier and retailer in each financing mechanism, compare the preferences of each player between the AF and RF models, and find a Pareto zone of a reverse factoring financing plan in which all players prefer model RF over model AP. We also conduct some numerical experiments to show how the payment ratio and payment term of model RF affect supply chain sustainability and efficiency.