Liquid−liquid equilibrium data have been determined experimentally for {1-methyl-3-octylimidazolium tetrafluoroborate + thiophene + hexane} and {1-methyl-3-octylimidazolium tetrafluoroborate + thiophene + cyclohexane}ternary systems at 298.15 K. The compositions of the ends of the tie-lines were obtained by gas chromatographicanalysis of phases at equilibrium. Data have been adequately correlated using the nonrandom two-liquid (NRTL)activity coefficient model despite this being an equation intended for nonelectrolyte solutions.