Greener prospective of soap production using natural products is a promising alternative for synthetic chemicals used in the soaps. Recently, valorization of antioxidant rich biomass wastes for soap formulation has received increased research attention. The present study reported the use of date syrup biomass waste (DSW) for the manufacture of soaps with enhanced bactericidal and antioxidant activity. DSW extract synthesis from Khalas date fruit type was optimized for operational parameters such as solvent type, temperature, and feed-to-solvent ratio. Maximum antioxidant activity of 605 ppm gallic acid equivalent was obtained for DSW extract obtained at 30 °C and feed-to-solvent ratio of 120 g/L using water as a solvent. Antioxidants assessment of pomace olive soaps modified with DSW extract showed an optimal extract concentration of 3 wt% for soap formulation. Inclusion of this optimal concentration of DSW extract decreased the pH and moisture content, with an increase in foam height, surface hardness, and total fatty matter of the resultant soaps derived from pomace olive, coconut, and palm oils. Physicochemical characteristics of the DSW extract included soaps were comparable to that of commercial turmeric soap. Furthermore, antibacterial assays demonstrated the enhanced bactericidal properties for DSW extract soaps against gram-positive Streptococcus pyogenes and gram-negative Pseudomonas aeruginosa bacteria. Overall, the results support the usage of DSW extract as an economic and effective natural antioxidant and antibacterial agent for soap preparation. © 2020 Elsevier B.V.