Solubility parameters are useful for estimating solubilities of solutes in ionic liquids when no solubility data are available. Solubility parameters are reported for nine ionic liquids; they were obtained from solubility data for a variety of solutes. The ionic liquids are 1-butyl,3-methylimidazolium hydrogen sulfate, 1-ethyl,3-methylimidazolium acetate, 1-methyl,3-trimethylsylilimidazolium chloride, 4-methyl,n-butylpyridinium tetrafluoroborate, ethylammonium nitrate, 1-ethyl,3-methylimidazolium bis(trifluoromethylsulfonyl)imide, 1-methyl,3-methylimidazolium bis(trifluoromethylsulfonyl)imide, 1-butyl,3-methylimidazolium bis(trifluoromethylsulfonyl)imide, and 1-ethyl,3-methylimidazolium ethylsulfate.