Abstract: A filtered drinking straw for providing on demand filtered drinking water is presented herein. The straw includes an elongated body defining a first end, a second end and an internal passage disposed there between. At least one filter is positioned within the internal passage of the body for reducing an amount of impurities that may be contained in the fluid as the fluid flows there through. The filter may include a core with a mix of granulated materials such as activated granulated carbon, chlorine grain, and zeolite. One or more retention structures may also be provided for retaining the filter within the body of the straw. The retention structure(s) include one or more internal projections, a mouth cap and/or end cap.