<p>Groundwater plays a crucial role as a primary source of drinking water in an urban setup like Siliguri Municipal Corporation (SMC). It faces serious health risk for nitrate and fluoride contamination due to rapid urbanization and poor waste management. This research aims to assess the quality of groundwater in the Siliguri Municipal Corporation (SMC) area to evaluate its suitability for drinking purposes and to analyse potential health risks associated with its consumption. The study sought to identify key physicochemical parameters influencing water quality, spatial variations, and to assess the health implications for different demographic groups of the study area. To achieve this objective, forty-eight (48) groundwater samples were analysed for pH, TDS, EC, TH, Fe⁺, Na⁺, Mg⁺, K⁺, Cl⁻, F⁻, NO₃⁻, and SO₄⁻. The Groundwater Quality Index (GWQI) model was used and the index exhibited 55.13% of SMC’s land is classified as poor and very poor, meaning the water is unfit for human consumption. After minor treatment, 44.87% of the water in the area is drinkable; without treatment, none of the water samples in the SMC area are suitable for human consumption. Principal Component Analysis (PCA) and Exploratory Factor Analysis (EFA) were used to confirm that ionic concentration and TDS are the primary drivers of groundwater variability, influenced by mineral dissolution and urban activities. Gibbs diagrams illustrated that 56.8% and 54.4% of groundwater samples fell in the rock dominance zone respectively, and 43.2% and 45.6% samples fell in evaporation domains. A total of 18 groundwater samples fall within the Na⁺/ (Na⁺ + Ca²⁺) ratio range of 0.6 to 0.8, which indicates relatively high sodium concentration compared to calcium, indicating septic tank leakage or other urban pollution. The Piper diagram shows that the study area is predominantly of the Ca–Mg–Cl type (74.51%), with 76.42% of samples rich in Ca²⁺ &amp; Mg²⁺ and 72.48% showing Cl⁻ &amp; SO₄²⁻ dominance, indicating hard water influenced by both geogenic and anthropogenic sources. The Total Health Hazard Index (THI) was also calculated for males (2.40), females (2.27), children (2.91), and the aged (2.51). The study reveals that children are most vulnerable, with fluoride and nitrate exposure doses of 0.0842 and 2.71&#xa0;mg/kg/day, followed by males (0.035 and 1.34&#xa0;mg/kg/day), females (0.033 and 1.34&#xa0;mg/kg/day), aged (0.034 and 1.55&#xa0;mg/kg/day) which indicates greater risk for children compared to other groups and leading to THI values above 1. Adults had lower but still concerning exposures, especially in northern and central zones where contamination reached nearly three times the permissible limits. The findings highlight an urgent need for mitigation, as 18% of samples exceeded acceptable fluoride level and 25% exceeded nitrate safety thresholds, posing long-term health risks. The health risks and groundwater quality assessment suggested that this area needs prevalent groundwater quality monitoring for long-term health management.</p>