We report on the use of solvatochromic probes to determine the microscopic polarity of water at their (average) solubilization sites in cationic micelles. The following probes were employed: 2,6-diphenyl-4-(2,4,6-triphenyl-1-pyridinio)-1-phenolate (RB), 1-methyl-8-oxyquinolinium betaine (QB), sodium 1-methyl-8-oxyquinolinium betaine-5-sulfonate (QBS), and 1-methyl-3-oxypyridinium betaine (PB). The cationic surfactants studied were cetyltrimethylammonium bromide, cetyldimethylbenzylammonium bromide, dodecyltrimethylammonium bromide, and dodecyldimethylbenzylammonium bromide. The microscopic polarity, E-T, kcal/mol, depends on structures of both probe and surfactant. PB, the most hydrophilic probe, does not partition into the micellar pseudophase, whereas RE, the most hydrophobic one, samples a much lower microscopic polarity than QB and QBS because of its deeper penetration into the cationic micelle. Polarities measured by (zwitterionic) QB and (anionic) QBS differ because the latter probe exchanges for the surfactant counterion. Our ET values refer to micelle-bound probes and are lower than literature values, which have been typically determined at [surfactant] = 0.05 mol L-1. Effective water concentrations at the solubilization sites of these solvatochromic probes have been calculated by using as references mixtures of water with each the following organic solvents: 1-propanol, dioxane (RB); ethanol, 1-propanol, acetonitrile, dioxane (QB and QBS). These water concentrations vary between 22.1 and 47.8 mol L-1, depending on structures of the probe, the surfactant, and the reference solvent mixture.