The magnetization of SmFe11Ti single crystals has been measured along the principal crystallographic directions in steady (14 T) and pulsed (43 T) magnetic fields. The fourfold symmetry axis [001] is an easy magnetization direction. The magnetization curves measured in directions perpendicular to [001] are remarkable in two ways: (i) They do not depend on orientation of H within the basal plane; (ii) at low temperature they are S shaped, with an inflection point at about 0.6 times saturation magnetization. These two facts enable us to conclude that three out of five crystal field parameters of SmFe11Ti are negligibly small; only A02 and A06 are essentially nonzero. A comparison with an isomorphous compound DyFe11Ti reveals a dramatic disparity of their crystal fields, especially as regards A44 , nearly zero in SmFe11Ti but outstandingly large in DyFe11Ti.