Surfactant compositions in an acidic or neutralized form containing a mixture of at least one polyoxyalkylenated phosphoric acid monoester and at least one polyoxyalkylenated diester and a nonionic polyoxyalkylenated compound wherein the phosphoric acid diester:phosphoric acid monoester molar ratio before neutralization, if carried out, is at least equal to 0.9:1 and the phosphoric acid monoester and phosphoric acid diester content is at least 1 mol %, preferably at least 50 mol % of said composition. The surfactant compositions are prepared by phosphatization of a nonionic polyoxyalkylenated compound at a temperature of from about 35.degree. to about 45.degree. C. followed by maturing at from about 40.degree. to about 60.degree. C., in a stirred turbulent state. The compositions are useful in the formulation of active substances in the form of microgranules and flowables.