This data set contains planar Particle Image Velocimetry measurement fields for the experiments described in the article titled "The instantaneous structure of a turbulent wall-bounded flow influenced by freestream turbulence: streamwise evolution" (doi:10.1017/jfm.2024.1008). The experiments were conducted in a water channel at the Norwegian University of Science and Technology. The setup includes an active grid to control freestream conditions. To analyze the evolution of the flow, the boundary layer was tested at four different streamwise locations for three grid sequences with freestream turbulence intensities up to 10.9%. Careful preprocessing was implemented to ensure high accuracy and minimal uncertainties. This work was funded by the Research Council of Norway (see funding information): Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the Research Council of Norway. The granting authority cannot be held responsible for them.