The producer choice between Bt and non-Bt cotton varieties should be based on the expected economic returns generated when using a variety rather than agronomic results alone. Producer concerns about the economic costs and returns associated with Bt cotton varieties led to a state-wide project in Georgia. The objective was to obtain independent, field-level research results from producer fields of Bt and non-Bt cotton varieties grown in close proximity and under similar production systems. Bt cotton varieties were found to produce an average yield of 104 pounds lint per acre more than the same producer's non-Bt variety grown in a similar production system. The number of spray applications for insect and plant growth control were reduced an average of 2.5 applications per acre on the Bt variety versus the non-Bt. For a cotton market price of $0.70 per pound of lint, the yield advantage would mean $72.80 of added gross returns per acre. Cost savings from the 2.5 fewer insect control applications would total $27.50 per acre, assuming an $11 cost per acre for materials and spraying. Average gross economic advantage in favor of Bt cotton would thus total about $100 per acre. Subtracting the $32 technical charge, Bt cotton varieties were still found, on average, to have a sizeable economic advantage over the non-Bt varieties selected.