There has been a shift in the paradigm of geotechnical engineering design from the working or allowable stress design (WSD/ASD) to limit state design (LSD) to better tackle the uncertainties in design and soil parameters. Using reliability-based design (RBD) methods, designers can quantify the risk of designs and make informed decisions to avoid the designs being excessively conservative. Thus, RBD can help reduce environmental impacts indirectly through the optimization of risk and performance of geotechnical structures. To incorporate environmental impact considerations in the design process, a strong understanding of the trade-offs between the engineering reliability and environmental sustainability of geotechnical structures is needed. This study aims to provide a comprehensive analysis of the relationship between reliability and global warming impact of drilled shaft designs. The impact of global warming is evidenced by the rise in Earth’s surface temperature resulting from the emissions of carbon dioxide and other greenhouse gases. In this study, the first-order reliability method (FORM) and life-cycle assessment (LCA) are used to investigate the relationship between reliability and global warming impact of drilled shaft designs, considering uncertainties in (i) soil properties, (ii) applied load, (iii) design equations, and (iv) pile dimension. Charts are developed for quick estimation of the global warming impact of drilled shaft designs that have different safety requirements, applied load, and design dimensions. The charts are useful for designers who do not have access to specialized software packages for conducting FORM and LCA and can be helpful for achieving a balance in the reliability, cost, and environmental sustainability of drilled shaft designs.