High-elevation wetlands are important indicators of environmental shifts caused by global climate change. These wetlands have the potential for disproportionately high biogeochemical cycling on the landscape, but little research has focused on these processes in subalpine or alpine wetlands. Our study aimed to characterize redox-active organic matter reduction, a known key control on carbon cycling in northern wetlands, to better understand the biogeochemistry of these ecosystems and impacts on carbon greenhouse gas production. We investigated the potential for redox-active organic matter reduction, and subsequent methane and carbon dioxide fluxes, at three different wetlands at Niwot Ridge Long-Term Ecological Research Site: subalpine peatlands, periglacial solifluction lobes, and alpine wet meadows. To study the differences in redox-active organic matter reduction potential across the three wetland types and at multiple depths, we carried out an anaerobic laboratory incubation for 63 days. We measured methane, carbon dioxide production, and redox-active organic matter reduction of samples on day 2, 7, 21, 28, 35, and 63 of the experiment. Redox-active organic matter reduction was significantly higher at the subalpine peatlands and the periglacial solifluction lobes than the alpine wet meadows (p < 0.05). There were no significant differences between the relative redox-active organic matter pools of the subalpine peatlands and periglacial solifluction lobes across depth (p > 0.05). These findings demonstrate that redox-active organic matter reduction is an important, overlooked biogeochemical process and an important control on methane production at these sites and adds to our understanding of how high-elevation, wetland ecosystems may respond to climate change.