The estimated propellant production cost per metric ton will be derived and presented for solar system transportation waypoints. Background on recent and ongoing space resource propellant supply models will be presented, with a review of architectural assumptions, costs and expected markets. Integrated economic and engineering models (Duke et al., 2003; Duke, Blair and Diaz, 2002; Lamassoure et al. 2003; and Blair et al., 2002) estimate production costs, expected productivity of the mining and processing system, reusable transportation element behavior, fuel depot activity and revenues based on projected market conditions. Results of these economic models are used to derive total and marginal unit costs for propellant at fuel depot facilities for the purpose of facilitating the commercial development of space and to aid program and logistic planning for human space exploration missions. © 2004 American Institute of Physics