Apparent molar volumes and viscosity B-coefficients for pyridoxine hydrochloride in aqueous tetrabutylammonium hydrogen sulphate (TBAHS) solutions were determined from solution density and viscosity measurements at T = (288.15-318.15) K and p = 101 kPa as a function of pyridoxine hydrochloride concentration. The standard partial molar volume and slopes, obtained from the Redlich-Meyer equation, have been interpreted in terms of solute-solvent and solute-solute interactions respectively. The viscosity data were analyzed using the Jones-Dole equation and the derived parameters A and B were interpreted in terms of solute-solute and solute-solvent interactions respectively. The standard volume of transfer and viscosity B-coefficients of transfer of pyridoxine hydrochloride from water to aqueous TBAHS solutions were derived to study various interactions in the ternary solutions. The activation parameters of viscous flow for the ternary solutions were also calculated and explained in terms of transition state theory. (C) 2016 Elsevier Ltd.