The finite difference time domain method is extended to include three-dimensional propagation in a saturated magnetized ferrite with an arbitrary direction of the biasing field. The recursive convolution method is used to include the frequency dependence of the ferrite. Both total and scattered field formulations are developed. This approach requires the additional storage of at most three complex numbers per cell. Transient scattering in two and three dimensions is used to demonstrate the accuracy of this approach. ¿ American Geophysical Union 1996