A recently developed methodology for evaluating solute functional group contributions to the partial molar compressibility of solution [Lockwood, D. M.; Rossky, P. J. J. Phys. Chem. B. 1999, 103, 1982] is used to examine solvation of methanol and ethanol in water. Additive contributions to the compressibility are resolved for the methyl and hydroxyl groups of each solute, and the results are shown to be the same for both solutes within statistical error. Further, the effect of each functional group on the solvent is found to be localized in the vicinity of that functional group, explaining the apparent independence of functional group contributions observed experimentally by other workers. The difference in partial molar compressibility between methanol and ethanol can be attributed to localized solvent perturbation by the methylene group in ethanol. For the potential functions employed, compressibilities calculated via classical molecular dynamics simulations are in best agreement with experiments performed at temperatures higher than those at which the simulations are performed. Implications of calculated alcohol group contributions for studies of more complex solutes, including biomolecules, are discussed.