Soil microbial communities control many of Earth’s biogeochemical cycles; however, much of what we know about microbial communities is confined to the upper soil layers. Subsoil microbial communities (> 20 cm in depth) present a vital knowledge gap in comprehensive understanding of soil health, biogeochemical cycling, and carbon storage in the face of ongoing global change stressors. Subsoil microbial communities are important because they remain understudied reservoirs of microbial activity. Emerging research shows that, when accounted for, their inclusion could significantly change estimates and models of biogeochemical cycling. Subsoil microbes are taxonomically and functionally distinct from their surface soil counterparts, with adaptations that allow them to survive in resource-limited conditions. We are yet to discover how subsoil microbial communities differ across large climate gradients and how this impacts Earth’s biogeochemical cycles. Furthermore, the responsiveness of subsoil microbial communities to experimental manipulations is undefined. As a variety of global change stressors (e.g., elevated temperatures, enhanced nitrogen deposition, increased wildfire activity) continue to escalate, understanding how the subsoil responds will become increasingly important. Recently, a critical mass of research on the subsoil microbial community has emerged allowing for a synthesis across ecosystems to determine the contribution of subsoil microbial communities to ecosystem functionality at multiple scales. This session aims to “lift up” subsoil microbes and present new opportunities and questions for future work in the subsoil. Given the interdisciplinary nature of this work, this session should be of interest to microbial ecologists, biogeochemists, ecosystem ecologists, and earth system modellers. We encourage participants to “think deeply” about soil microbial communities and join us in this session.