The compressive clamping pressure at the interface of gas‐diffusion‐layer (GDL) and current collector decreases the contact resistance between them though it reduces the porosity and surface roughness of electrocatalysts, which would in turn decrease the efficiency of an electrolyzer. We explore these issues of trade‐off between porosity versus contact resistance and provide a design heuristic for optimum clamping pressure. The present work provides an estimate of the optimal value of clamping pressure for an alkaline water electrolyzer having membrane electrode assembly (MEA), taking account of the variation in porosity of catalyst layers and contact resistance obtained via half‐cell studies performed at different pressures. Towards this, we define the performance‐index (Φ) which is the ratio of Faradaic current density and resistances resulting from contact‐interfaces in electrolyzers and we suggest that the maxima in Φ corresponds to optimum clamping pressure.