Abstract The elastic diffuse neutron scattering of the non-stoichiometric carbides TiC 0.76 and NbC 0.73 has been measured at room temperature, in the (110) reciprocal lattice plane, for 0.2⩽q = 4π sin O/λ⩽4 A ̊ -1 . The Cowley-Waren short-range order parameters were obtained for the eight first shells of neighbours of the metalloid f.c.c. sublattice. The degree of short-range ordering was found much larger in NbC 0.76. Strong displacements of the metal atoms towards their first neighbour carbons occur in both cases.