A method and system for the design and implementation of an optimally factored interpolated finite impulse response (IFIR) filter is presented. Techniques used to increase the implementation efficiency of the filter include joint sequencing of the filter stages, use of an nested IFIR filter, taming of a stage by relocation of that stage, fusing two or more stages together to form a single stage, and manual manipulation of a post-stage multiplier. IFIR filters using this approach may be realized as low pass filters or high pass filters, and in either analog or digital form.