Examples disclosed herein relate to single cell transfection with interchangeable reagent. The present disclosure relates generally to a device, method, and system for single cell transfection including a transfection chamber on a transfection chip. The example system may include a fluidic channel located on the transfection chip for guiding a cell towards the transfection chamber, the fluidic channel sized to allow no more than a single cell to arrive at the transfection chamber at a time. The example system may also include a reagent receiver located on the transfection chip guiding received reagent towards the transfection chamber and intersecting with the path of the fluidic channel.