The solvated molecular salt, C13H30N3+·C20H36BSi4−·C4H10O, was obtained by the reaction of trimethylsilylethyne with boron trichloride in the presence oftert-butyllithium, followed by ion metathesis. The cation exhibits positional disorder and one of the Me3Si groups shows rotational disorder. No significant directional intermolecular interactions are observed.