Reaction of [Ru(η⁶-p-cymene)Cl₂]₂ with two equivalents of [Ph₄P][Cl] in CH₂Cl₂ yields [Ph₄P][Ru(η⁶-p-cymene)Cl₃], containing a trichlororuthenate(II) anion. In solution, an equilibrium between the product and [Ru(η⁶-p-cymene)Cl₂]₂ is observed, which in CDCl₃ is nearly completely shifted to the dimer, whereas in CD₂Cl₂ essentially a 1:1-mixture of the two ruthenium species is present. Crystallization from CH₂Cl₂/pentane yielded two different crystals, which were identified by X-ray analysis as [Ph₄P][Ru(η⁶-p-cymene)Cl₃] and [Ph₄P][Ru(η⁶-p-cymene)Cl₃]⋅CH₂Cl₂.