The present disclosure relates to fluid delivery devices for supplying a fluid, e.g., a flush medium, to a medical device, e.g., a vascular access device, inexpensively. The fluid delivery device includes a collapsible body defining a fluid reservoir and a connector for securing the fluid delivery device to the medical device. The collapsible body can include a bellows or pleated structure. In addition, structure including levers or plungers can be provided to collapse the body.
