This article presents a noniterative and parallel finite element technique that is tailored for a wide class of electromagnetic boundary problems, covering both quasi-static and time-harmonic regimes. This approach, called the characteristic basis finite element method, combines the domain decomposition technique with the use of characteristic basis functions that are generated by employing a finite number of point charges or dipole-type sources, depending upon whether work is being done in a quasi-static or a time-harmonic regime. Two major advantages of this method are considerable reduction in the matrix size and convenient parallelization, both of which make possible the direct solution of multi-scale problems in an efficient manner. For the static case, the problem of computing the capacitance matrices of 3D interconnects in integrated circuit packaging is considered. For the time-harmonic case, the proposed method is applied to 3D electromagnetic scattering problems. The accuracy of the proposed technique has been validated via a number of numerical simulations, covering a wide variety of configurations.