A reversed-polarity capillary electrophoretic method based on application of sodium dodecyl sulfate (SDS) micelles as the carriers was developed for separation and determination of Fexofenadine (FXN) hydrochloride and its three major structural impurities in bulk and a tablet dosage form. CE analysis was performed using untreated fused-silica capillary of 50 µm internal diameter and 75-cm total length (25-cm effective length). The voltage applied of −25 kV at 25°C, and the detection wavelength was set at 225 nm. The running buffer was a 150 mM phosphate buffer at pH = 3.0, containing 22% v/v acetonitrile and 25 mmol SDS. Terfenadine was used as the internal standard (IS). The proposed method was found selective for determination of the main drug and its major impurities. The limit of quantification (LOQ) for FXN and impurities D10, D11, and A were found 70 µg/mL, 50 µg/mL, 80 µg/mL, and 100 µg/mL, respectively. The regression data obtained from the calibration plots indicated linear relationship (r2 = 0.997) over the concentration range of 70–500 µg/mL of FXN. Repeatability and reproducibility of the method, assessed as intra-day and inter-day variation and expressed as RSD (%), were less than 4% for relative peak area. Then, the method was applied for the determination of FXN in bulk and a tablet dosage form.