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For the study, two low-cost handheld GPS receivers were compared to a DGPS receiver. A combine equipped with a yield monitoring system was configured so that yield data could be collected simultaneously using a low-cost handheld GPS receiver and a DGPS receiver. Results in 2000 showed average relative positioning differences of 1.78 meters and that similar yield maps could be created. Due to the limited hectares harvested in 2000 further analysis was desired. During the 2001 fall harvest, 212.2 hectares of corn and 283.7 hectares of soybeans were harvested using the above mentioned yield monitor configuration. In 2001, average relative positioning differences of 2.97 meters was obtained between GPS receivers. Yield maps were produced from the same field using standard yield mapping techniques. Comparisons were made between the maps of how similar they were at showing variability and yield in Mg/ha. Visually one could distinguish yield data collected between the two low-cost GPS receivers. Using regression analysis for map comparison, R-squared values ranged from 0.3 to 0.9 with a mean of 0.73.