The complex interactions of magnetic field with crude oil have always posed challenges in its commercial implementation as a wax deposition control method. In the present work, changes in viscosities of three crude oil samples subjected to varying magnetic fields and time of exposure were measured. The resultant data along with the data from literature was used to develop phenomenological models. These models related the final viscosity with the wax %, magnetic field, time of exposure and wax appearance temperature. The model parameters suggested that the amount of wax and the exposure time were the governing factors for viscosity reduction. Such models would help in the tuning of magnetic field strength and exposure time to obtain a desired viscosity reduction. This would help in the design of better oil transportation systems, thereby generating confidence in the method. © 2022