Four field experiments were established in 1988 in Arizona to evaluate the effects of banded phosphorus (P) fertilizers on cotton. Two sites involved Upland cotton (Gossypium hirsutum L.) and two sites with Pima (G. barbadense L. var Pima S-6), with one of each located near Marana, AZ (Vinton-Anthony sandy loam), and also one of each located near Coolidge, AZ (Mohall sandy loam). At the Marana studies, P was applied 6 in. directly below the zone of seed placement at the time of listing and at the Coolidge sites, P was applied 6 in. below and 2 in. to the side of the zone of seed placement after listing, but before planting. In all cases, the P source was 10-34-0 at rates of 0, 30, and 65 lb. P₂O₅ acre. At the Marana location, a treatment of banded 10-34-0 at 30 lb. P₂O₅ acre 1 plus a foliar application of 10 lb. P₂O₅, acre^-1 (early bloom) as 10-34-0 was included in both the Upland and the Pima experiments. Plant measurements for plant height, flower numbers, node numbers, boll numbers, and nodes to first fruiting branch were taken to evaluate plant response throughout the season. Plant tissue samples were also taken for leaf petiole PO₃-P and leaf blade total P analysis. Lint yield measurements were also taken. No statistically significant (P < 0.05) differences were found among any of the treatments for any of the measured parameters, except in the petiole PO₃-P levels from the Upland study at Coolidge on the second sampling date.