The crystal and molecular structure of dichloro(diphenyl)tin has been determined by single-crystal X-ray diffraction methods using the intensities of about 3800 reflections measured by counter diffractometry. The crystals belong to the triclinic system, a= 15·905(2), b= 9·367(1), c= 9·034(1)Å, α= 76·89(1), β= 93·21(1), γ= 94·78(1)°, space group P, and Z= 4. The structure was solved by Patterson and Fourier methods and refined by block-diagonal least-squares techniques, using individual anisotropic thermal parameters, to R 0·040. All hydrogen atom positions were located but were not refined. There are two discrete molecules of Ph2SnCl2 in the asymmetric unit with identical geometry. The mean bond distances are: Sn–Cl 2·346(2), Sn–C 2·114(3), and C–C 1·387(13)Å. Mean values for the valence angles at the tin atom are: Cl–Sn–Cl 100, Cl–Sn–C 107, and C–Sn–C, 125·5°. There is no molecular association in the crystal, the shortest Sn ⋯ Cl contact being 3·77 Å. The interpretation of Mössbauer spectroscopic results in terms of a polymeric network in the crystal structure involving six-co-ordinate tin is thus shown to be incorrect.