This paper investigates numerically and experimentally the performance of a single stage wire-duct electrostatic precipitators (WDEP) as influenced by different geometrical and operating parameters. To numerically solve the governing equations, namely Poisson’s and the current continuity equations, the finite element method (FEM) and a modified method of characteristics (MMC) were used. One major advantage of the present work over those reported in the literature is that the characteristic lines follow the FE grid pattern which results in fast convergence and reduction of the computational time. To verify the results experimentally, a proto-type WDEP was successfully designed and fabricated at the research institute of KFUPM (RI-KFUPM). The experiments were carried out under laboratory conditions and a smoke of fired coal was used as a source of seed particles of PM10 category (around 78% of particles lying below 10 μm). The results show how different parameters (such as discharging wire radii’s, wire-to-wire spacing and wire-to-plate spacing as well as the fly ash flow speed and applied voltage polarity) influenced the corona power loss and current density profiles. An indication of the effectiveness of this approach was carried out through a comparison of previously computed results and previously as well presently obtained experimental data.