Studies on the characterization and performance of residual sugarcane bagasse ash (SCBA) obtained from high-temperature cogeneration boilers in concrete are highly limited. This study investigated the pretreatment process and optimization of SCBA collected from high-temperature boilers by various physicochemical methods. The effect of recalcination and grinding on the physical and mineralogical properties of SCBA were also examined. The percentage replacement of cement with SCBA was optimized using packing density and flow. The performance of optimized binder with combinations of cement and SCBA was validated through compressive strength of mortar specimens. From the results, it was observed that SCBA from high-temperature boilers can be used as a supplementary cementitious material with minimal processing efforts and a 15% level of replacement is suggested as the optimum level for SCBA-blended cement. Based on the investigation, a framework with a step-by-step procedure including pretreatment and optimization methods is suggested for the use of SCBA. © 2021 American Society of Civil Engineers.