Swimming motility is a flagellum-dependent form of movement observed in the Gram-negative bacterium Pseudomonas aeruginosa. Swimming motility is defined as the movement in liquid or low-viscosity conditions (up to 0.3 % agar concentration). Unlike swarming motility, swimming motility requires a functional flagellum, but neither quorum sensing (QS) systems nor biosurfactants. While swimming motility can also be observed via microscopy, here we describe a reproducible plate-based method.