Abstract The transesterification reaction of glycerol with dimethyl carbonate (DMC) into glycerol carbonate presents an attractive route for simultaneous biodiesel by‐product valorization and indirect CO 2 utilization. In this study, a heterogeneous catalyst was developed for this reaction by grafting 1,5,7‐triazabicyclo[4.4.0]dec‐5‐ene (TBD) on mesoporous SBA‐16 silica (TBD@SBA‐16), combining strong basicity with high surface area and structural stability. Various physicochemical characterizations (BET, TGA, FTIR, NMR, SAXS, TEM) confirmed the successful formation, functionalization, and thermal stability of samples. The forward reaction was identified as endothermic and entropy‐driven, with an activation energy of 23.3 kJ/mol in the presence of homogeneous TBD, as validated by kinetic and thermodynamic analyses. This reaction was monitored for the influence of reaction parameters, including catalyst loading, reaction time, temperature, and DMC/glycerol molar ratio. Under optimal conditions (3 wt% catalyst, 90 °C, 2 h, 4:1 DMC: glycerol molar ratio), glycerol conversion reached 97% with glycerol carbonate yield exceeding 98%. The grafted catalyst displayed higher selectivity and operational practicality compared to homogeneous TBD. Reusability studies over five successive cycles revealed just a minor activity loss (∼4%) and low TBD leaching. These findings highlight the efficiency and stability of TBD@SBA‐16 as a viable heterogeneous catalyst for the selective synthesis of glycerol carbonate.