The economics of hauling manure as a substitute for commercial fertilizer in the production of cultivated crops was investigated using a computer model that accommodates variables such as hauling distance, machinery complement, hauling speed, labor use, spreading time, and crop response. Machinery complement and labor requirements were defined and budgeted for three farm-feedlot scenarios, namely: a very large farm-feedlot (>?1000 head capacity), a large farm-feedlot (500?1000 head capacity), and a small farm-feedlot (500 head capacity). Results indicate that manure, valued for its N and P2O5 nutrient content, is generally an economical substitute for commercial fertilizer when hauled up to 15?km from feedlot sources. Large farm-feedlots, hauling manure less frequently and employing a farm tractor with front-end loader and single axle truck with a manure box, can haul manure up to 15?km and recover all costs. Small farm-feedlots employing a farm tractor with front-end loader and pull-type manure spreader can economically haul manure up to 15?km if non-cash costs and labor charges are disregarded. Alternatively, custom corral cleaners can be hired to haul manure up to 18?km in competition with commercial fertilizer on an N and P2O5 nutrient value basis. The yield benefits of manure increased the breakeven hauling distances dramatically for some crops. A need for more research to determine economic optimum manure application rates for various crops is identified. Key words: Fertilizer, feedlot manure, fertilizer economics, animal wastes