Abstract The pressure-volume dependences of UP, USb and UTe have been determined by X-ray powder diffraction in a diamond anvil cell. To obtain reliable variations it is essential to account for the effects of anisotropic stress components. UP maintains its cubic NaCl-type structure at least up to 25 GPa while USb undergoes a cubic NaClCsCl type transformation at 8 GPa. The experimental data have been fitted to a Birch equation of state and the bulk moduli so obtained are compared to theoretical values. The presence of a Kondo effect in UTe is assumed to be responsible for its low bulk modulus.