The sorption of several organic phosphates were measured on soil, peat and other organic and inorganic materials. The behavior of the phosphates on these materials differed from that reported for similar studies on acidic soil materials. In contrast to the sorption on acidic soils, where sorption maxima occur, the sorption on basic soils may reach a maximum but does not decline thereafter. Both clay and organic matter content govern the amount of sorption but calcium seems to account for the differences observed from those on acidic soil materials