This paper presents the modeling and design methods of true-time distributed microelectromechanical systems transmission lines (DMTLs) making use of periodic structure theory. New contributions to the analysis and reduction of the microelectromechanical systems (MEMS) shunt capacitors parasitics are also introduced. A prototype of a digital DMTL has been fabricated and measured, showing very good agreement with the comprehensive circuit model used for the design. It is believed that the periodic structure approach presented could be useful for other microwave periodic MEMS devices.