This study accounts for groundwater quality in parts of Hyderabad and adjoining Medchal-Malkajgiri districts, Telangana, southern India. Due to rapid northward and eastward expansion of the city, groundwater quantity and quality are experiencing severe deterioration. In this study, in total, 48 samples each have been collected during pre- and post-monsoon periods, respectively from bore-wells (n = 24) in 2022 to test the physico-chemical parameters namely pH, EC, TDS, TH, Na+, K+, Ca2+, Mg2+, F−, Cl−, (CO3)2−, HCO3−, NO3−, SO42− through standard methods for determining the suitability for everyday purposes such as domestic, irrigation and industrial. The general order of abundance of prominent anion and cation species in groundwater is F− > NO3− > SO42− > Cl− > HCO3− and K+ > Mg2+ > Ca2+ > Na+, respectively. The results show that a considerable number of samples have excess nitrate content as high as 49 ppm in pre-monsoon (Alwal) and 209 ppm in post-monsoon (Alwal, Madhapur, Mushirabad, Dundigal and Sundarnaagar). The fluoride content is higher than one ppm in 50% of pre-monsoon (Alwal, Balanagar, Qutubullapar, Malkaljgiri, Sundarnagar, Mehdipatnam, Bollarum, Dundigal and Nizampet) and 45% of post-monsoon samples (Qutubullapur, Balanagar, Malkajgiri, Subhashnagar, Mushirabad, Mehdipatnam, Dundigal, and Alwal). Based on EC (electrical conductivity), high Na%, and SAR (Sodium Absorption Ratio), the pre-monsoon samples have been classified into C2S1, C3S1, and C3S2 types showing ‘high salinity hazard categories for regular domestic and irrigation usage. Geogenic factors such as hard granitic basement, lack of fracture system, reduced natural recharge and anthropogenic activities are believed to be the causes for the deterioration of groundwater quality in the study area despite heavy rainfall during the year 2022.