Three simple, economical, precise and Accurate UV Spectrophotometric methods have been developed for the estimation of Montelukast sodium in bulk and pharmaceutical formulations. Method A involves measurement of absorbance of solution at 344.30 nm in methanol. Method B involves integrating area under curve in the wavelength range of 342.93 nm-343.75 nm and is used to construct calibration curve. Method C is first order derivative spectroscopy method, in which first derivative amplitude at 347.91 nm is measured. Linearity for detector response was observed in the concentration range of 5-25 μg/ml for all the three methods in methanol. The results of analysis have been validated as per ICH analytical method validation guidelines. Accuracy, precision and recovery studies were carried and confirmed the validity of the proposed methods.