W ATER scarcity presents a significant challenge for viticulture in arid and semiarid regions, making it necessary to adopt effective and sustainable grape production strategies. It is crucial to search for alternatives to water-saving practices. This study evaluated the effects of deficit irrigation (DI) and antitranspirant application on 'Crimson Seedless' grapevine performance. DI consisted of five treatments: traditional irrigation (full irrigation), L1 (75% of full irrigation throughout the season), L2 (75% of full irrigation except during berry enlargement, which matched traditional irrigation), L3 (50% of full irrigation), and L4 (50% of full irrigation except during berry enlargement, which matched traditional irrigation). Each treatment included foliar spraying with either potassium silicate, linseed oil, or water (as the control antitranspirant). Grapevines under DI achieved the highest crop water productivity, fruit soluble solid content (SSC), total phenols, antioxidant capacity, and total anthocyanins, with no significant reduction in fruit yield except in L4 (severe deficit). Antitranspirants application improved fruit yield, NPK content, total phenols, and reduced antioxidant capacity. Compared to control, DI treatments saved 25%, 13%, 50%, and 26% of irrigation water for L1, L2, L3, and L4, respectively, also reducing irrigation costs. These practices enhance sustainability by minimizing water waste and power use for irrigation. Additionally, foliar antitranspirant application reduced antioxidant capacity and improved chlorophyll and nutrient contents, and subsequently fruit yield, besides fruit quality such as SSC, anthocyanins, and total phenols. Deficit irrigation combined with antitranspirants effectively conserved irrigation water and enhanced fruit quality without compromising yield under arid and semi-arid grape production conditions.This approach represents a promising strategy to improve water productivity and support sustainable viticulture under water and climate