The present invention relates to pesticidal compositions compris ing 2,3-dihydro-2,2-dimethylbenzofuran-7-yl (dibutylaminothio)methylcarba mate, namely benzofuranyl methylcarbamate, commonly known as carbosul fane, of structural formulan (I). The present invention deals more particularly with compositions comprising this active compound at a high concentration, which makes it the most economical product for sale, more stable during storage and more of fective in small quantities, and it may be further combined with one or more inerts. The present invention further discloses a process for preparing said compositions and a process for controlling insects/mites/nematode. The applications for these formulations include the treatment of seeds and leaves. In the latter case, in addition to the diluting agent, a mixtu re of anionic and non-ionic surfactants have been included in the formulation, so that the solution will become self-emulsifying upon being added to water.