This research delves into the integration of economically sustainable materials—Portland limestone cement (PLC) and recycled glass powder (GP)—into ultra-high-performance concrete (UHPC) formulations. The emphasis is on mitigating UHPC’s reliance on high-cost, high content of cement, and proprietary additives, which elevate both the expense and environmental impact of infrastructure projects. By evaluating the effects of PLC and GP on the structural performance of UHPC, the study aims to provide affordable, locally sourced, and customizable options. This study investigates the enhancement of UHPC by testing six mortar mixes that contrast the use of ordinary Portland cement (OPC) with the more sustainable PLC, enriched with silica fume (SF) and recycled glass powder. The introduction of glass powder notably increased UHPC’s compressive strength, and PLC mixes showed enhanced early strength and reduced shrinkage. This underscores the potential of PLC and recycled glass for making UHPC more sustainable, while highlighting their beneficial roles in enhancing structural properties, marking a stride toward more eco-friendly construction materials.