A field experiment was conducted during Kharif season of 2020-21 at Agricultural Research Station, Keshwana, Jalore, Agriculture University, Jodhpur (Rajasthan) with an objective to find out the appropriate date of sowing of major contingent crop for the area with respect to late-early onset monsoon. Factorial Randomized Complete Block Design with three replications was being used during this study. The treatments consists of three sowing window viz;15 July, 25 July, 4 August and four contingent crop viz., Mungbean (F1), Mothbean (F2), Sesamum (F3), Clusterbean (F4). The study revealed that Mungbean have better performance during July 15nd, July 25st and August 4th realizing higher yield (740, 429 and 280 kg haâ1, respectively) as compared to Clusterbean, Mothbean, and sesamum. Mungbean is the best suitable contingent crop for deferred sowing condition in the transitional plain of luni basin of Western Rajasthan