<p>Hydrological modeling plays a central role in the sustainable management of water resources by helping researchers and decision-makers understand, simulate, and predict watershed behavior under changing climatic and land-use conditions. Among the available models, the Soil and Water Assessment Tool (SWAT) has become one of the most widely used semi-distributed, physically based hydrological models worldwide. Developed in the early 1980s and continuously refined over the past three decades, SWAT has evolved significantly, culminating in its latest version, SWAT+, which offers improved structural flexibility and enhanced process representation. This review provides a detailed overview of SWAT’s development, core structure, data requirements, calibration and validation strategies, and commonly used performance indicators. It also compares SWAT with three prominent hydrological models (HEC-HMS, MIKE-SHE, and VIC). The comparison is based on eight key criteria, including physical representation of processes, spatial discretization approach, open-source accessibility, capacity to simulate multiple hydrological processes, computational efficiency, calibration complexity, water quality integration, and breadth of documented global applications. Published studies from across the world, including extensive research from the Indian subcontinent, highlight SWAT’s adaptability across varied watershed scales and climatic conditions. Major application areas include streamflow simulation, sediment and nutrient transport analysis, climate change impact assessment using CMIP5 and CMIP6 projections, land-use change evaluation, best management practice assessment, and integrated groundwater-surface water modeling through SWAT-MODFLOW coupling. Despite certain limitations, emerging developments such as SWAT-machine learning integration present promising opportunities. Overall, SWAT remains a highly suitable and versatile model for watershed-scale hydrological research and management applications.</p>