We present the preparation of tert-butyldiphenylsilanes differing in one functional group. The molecular structures of the phenyl (3), methoxy (4), and amino derivatives (5) were elucidated by single-crystal X-ray diffraction analysis and their crystal packing investigated by Hirshfeld surface analysis along with 2D fingerprint plots. In the all-C derivative 3, the high symmetry dependence of the crystal packing enables a multitude of directional C(methyl)-H....C(pi) interactions between the tert-butyl and phenyl groups. The methoxy derivative 4 is characterized by considerably short H...H contacts possibly resulting from pre-orienting C(aryl)-H...O and C(aryl)-H...C(pi) hydrogen bonds. In the amino derivative 5, the nitrogen atom is not involved in intermolecular interactions, instead dispersive H...H contacts might become more important for the crystal cohesion. These findings once again underline the pronounced lone electron pair density transfer from the nitrogen atom towards the silicon atom.