In this paper, the authors present the first known Timing-Error Detection (TED) microprocessor able to operate in subthreshold. Since the Minimum Energy Point (MEP) of static CMOS logic is in subthreshold, there is a strong motivation to design ultra-low-power systems that can operate in this region. However, exponential dependencies in subthreshold, require systems with either excessively large safety margins or that utilize adaptive techniques. Typically, these techniques include replica paths, sensors or TED. Each of these methods adds system complexity, area and energy overhead.