<p>Hydrological Ecosystem Services (HES) such as water supply and purification are fundamental for sustaining human well-being and guiding sustainable land and water management, especially in regions facing water scarcity and intense anthropogenic pressure. Here we applied and compared the new version of the Soil and Water Assessment Tool (SWAT+) and the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) in the Campo de Cartagena (southeastern Spain), an intensively cultivated catchment. Both models, as well as a coupled version (SWAT+InVEST), were evaluated for their ability to simulate water yield and nutrient export, assessing performance, suitability, and complementarity under conditions of high human pressure, water scarcity, and ecological fragility. Unlike previous comparative studies focused on topographically diverse or forested basins, our work offers new insights into model behaviour in semi-arid and heavily modified landscapes. InVEST tended to overestimate water yield and underestimate nutrient export, while SWAT+ produced more realistic estimates for both HES. By coupling both models, we derived intermediate values that helped reduce the uncertainty of the InVEST model. Our findings offer guidance on model selection based on environmental complexity, data availability, and the trade-off between accuracy and usability. SWAT+ shows greater reliability in complex environments, while InVEST remains useful for broad-scale or rapid assessments in less demanding catchments. This study improves the reliability of HES assessments in catchments under intense anthropogenic pressure and supports more targeted ecosystem service management in semi-arid regions.</p> Graphical Abstract <p></p> <p>This graphical abstract summarizes the comparative evaluation of Hydrological Ecosystem Services (HES) in the Campo de Cartagena basin (southeastern Spain), an intensively cultivated and water-scarce region. The visual design illustrates the modelling framework tested through three approaches: SWAT+, InVEST, and their coupled version (SWAT+InVEST). Dotted lines emphasize the HES of water supply and purification, represented by their key descriptors: water yield and nutrient export (nitrogen and phosphorus). A consistent color scheme separates the HES descriptors horizontally, while the results from the different models are organized vertically, allowing direct comparison of their performance. The graphical abstract also integrates the main input data (climate data, agricultural practices, and geospatial datasets) used in the modelling process, providing a clearer overview of the data flow from inputs to outputs. In addition, color scales have been included for each variable (water yield, nitrogen export, and phosphorus export) to enhance visual interpretation and quantitative comparison. The figure highlights the distinct behaviour of each approach: InVEST tends to overestimate water yield and underestimate nutrient export, SWAT+ produces more reliable estimates under complex conditions, and the coupled framework provides intermediate outcomes that reduce the uncertainty associated with InVEST. This graphical abstract clearly links the study context, modelling process, and main findings, making the core contributions and conclusions easy to understand</p>