This study describes an efficient and simple technique for the synthesis of four new quinazolinone reactive disperse dyes, which include 1,3,5-trichlorotriazine (cyanuric chloride) group from quinazolinone and various substituted primary aromatic amines. The structures of the dyes were confirmed and elucidated by mass spectroscopy, UV-visible, FT-IR, 1H-NMR, 13C NMR, and CHN analysis. Theoretical values of all produced colors and observed data were in good agreement with the proposed chemical structure. The fabric's dyeing properties, color representation, dye exhaustion and fixation, and fastness properties are determined. These dyes have proven to be successful in dyeing blend fabrics, which are composed of 70% polyester and 30% cotton. Colorimetric data, exhaustion, and fixation investigations have produced outstanding results. These dyes have the benefit of being relatively easy to synthesize, and scaling them up is possible, favoring industrial dyeing applications. Additionally, the UV protection factor of the dyed fabrics was examined, and the results demonstrated that these dyes provided outstanding UV protection.