A simple, precise, rapid, and accurate RP-HPLC method was developed for the simultaneous estimation of Atenolol, Hydrochlorothiazide, and Losartan Potassium in pharmaceutical bulk drugs and tablet dosage forms. The method was developed by using HPLC (Shimadzu LC2010-CHT) with UV detector and Symmetry C18 (4.5 x 100mm, 5µm, make: waters) at 1.2 ml/min flow, column temperature – 27°C and a mixture of Methanol and water in the ratio of 65: 35 v/v as Mobile phase and diluent at 225nm wavelength, injection volume of 20µl with Isocratic flow for 10minutes run time. The accuracy studies show that % recovery for Atenolol, Hydrochlorothiazide, and Losartan Potassium at 50%, 100%, and 150% were found to be within 98-102%. Retention times were found to be 1.467 min, 2.208 min and 3.292 min for Atenolol, Hydrochlorothiazide and Losartan Potassium respectively.