We present a hybrid chip of polymer and stainless steel designed for high-throughput continuous electroporation of cells in suspension. The chip is constructed with two parallel stainless steel mesh electrodes oriented perpendicular to the liquid flow. The relatively high hydrodynamic resistance of the micrometer sized holes in the meshes compared to the main channel enforces an almost homogeneous flow velocity between the meshes. Thereby, very uniform electroporation of the cells can be accomplished. Successful electroporation of 20 million human dendritic cells with mRNA is demonstrated. The performance of the chip is similar to that of the traditional electroporation cuvette, but without an upper limit on the number of cells to be electroporated. The device is constructed with two female Luer parts and can easily be integrated with other microfluidic components. Furthermore it is fabricated from injection molded polymer parts and commercially available stainless steel mesh, making it suitable for inexpensive mass production.