Abstract: A simple, precise, accurate stability-indicating gradient reverse phase ultra-performance liquid chromatographic (RP-UPLC) method was developed for the quantitative estimation of purity of Telmisartan drug substance and drug products in bulk samples and pharmaceutical dosage forms in the presence of its degradation products and impurities. The present method was developed using Waters Aquity BEH C18 (100 mm x 2.1 mm, 1.7 µ) column with mobile phase containing a gradient time programme of the solvents A and B. The wave length selected for monitoring eluted compounds were monitored at 290 nm, the run time was within 10 min, which Telmisartan and its seven impurities were well separated. Telmisartan was found to degrade significantly in acid stress condition when it was subjected for various stress conditions. The degradation products were well separated from main peak and its impurities, proving the stability-indication of the method. The present method was validated as per international conference on harmonization (ICH) guidelines with respect to precision, specificity, linearity, limit of detection, limit of quantification, accuracy, and robustness.