The crystal and molecular structure of the title compound has been determined from single-crystal X-ray diffractometer data by Fourier methods and refined by anisotropic block-diagonal least-squares to R 0.054 for 4 065 independent observed reflections. Crystals are monoclinic, space group P21/n, with cell parameters a= 10.935(9), b= 39.191(11), c= 13.738(7)Å, β= 107.33(7)°, and Z= 8. The two crystallographically independent molecules are stereochemically equivalent (there is only a small difference in the orientation of a benzene ring) and the metal atom has a somewhat distorted octahedral co-ordination, with two pairs of like ligands mutually trans. Technetium–ligand bond distances are: Tc–Cl (trans to P) 2.46(1), Tc–Cl (trans to Cl) both 2.33(1), Tc–P (trans to Cl) 2.42(1) and Tc–P (trans to P) both 2.47(1)Å. The noticeble trans-influence of the phosphine ligands on Tc–Cl bonds is discussed.