The effects of finite temperature and ultrastrong magnetic field on the masses and radii of white dwarfs are investigated. We have considered a relativistic free Fermi gas of electrons embedded in strong Landau quantizing magnetic fields and at finite nonzero temperatures for the Equation of State (EoS). Due to the magnetic field, the total pressure of the electron gas and the field itself becomes anisotropic. This anisotropy results in the deformation of magnetized white dwarfs from spheres to oblate spheroids. This deformation is accounted in the presence of a deformed Schwarzschild metric known as the \(\gamma \) -metric. Stable super-Chandrasekhar masses \(({>}5M_{\odot })\) are obtained. We found that for a fixed central density and temperature, as the central magnetic field increases, the mass decreases and the equatorial radius increases. We also observed that the maximum mass and its corresponding equatorial radius decrease with the increase of the central magnetic field. Moreover, at a fixed temperature, the maximum mass occurs at a higher central density as the central magnetic field increases. This shows that increasing magnetic field, hence increasing anisotropy, softens the EoS and increases compactness of the star. Conversely, increasing the temperature leads to increase in both mass and radius, counteracting magnetic field effects by stiffening the EoS and decreasing the anisotropy. The effects of temperature are more prominent for lower magnetic fields and lower central densities.