Densities and viscosities at six temperatures in the range (298.15 to 343.15) K and refractive indices at nine temperatures in the range (293.15 to 333.15) K are reported for aqueous solutions of 1-amino-2-propanol (monoisopropanolamine (MIPA) or 1-AP). Excess molar volumes, viscosity deviations, and refractive index deviations were calculated from the measurement results and correlated as a function of composition using the Redlich−Kister relation and polynomial equations. Partial molar volumes at infinite dilution were determined from the apparent molar volumes. Negative values for excess molar volumes and molar refraction changes are observed over the whole composition range, whereas viscosity data exhibit both negative and positive deviations. Cross-associated hydrogen bonds forming between 1-AP and water contribute to the deviations in the properties with respect to mole fractions and temperatures.