Indus Basin is the second largest river basin in Asia shared by China, India, Pakistan and Afghanistan. Rapid climatic changes and exponential population growth have put tremendous pressure on the already depleting water resources in Indus Basin. The absence of supra‐national authority and a basin‐wide cooperation agreement is further exaggerating Basin's challenges. Moreover, an already existing Indus Water Treaty, a bilateral treaty signed between India and Pakistan is proving to be insufficient to regulate the water supply amidst the growing political tensions among the Indus riparian. To address this cross‐boundary issue, armed with game theory‐based strategies, this research proposes optimal water allocation solutions. The study adopted Bankruptcy and Asymmetric Nash bargaining solutions to determine optimal water allocations/Pareto‐optimal solutions. The results show that the optimal allocation for Pakistan and India are 181.95 and 101.95 km3 respectively, while for Afghanistan and China, the optimal allocation was found to be 2.99 and 0.11 km3 respectively. The sensitivity analysis reveals that the water allocations of Pakistan and India are sensitive to their respective changes in water claims, while insensitive to the changes in water claim of Afghanistan and China. The findings of the study can be used for negotiations and have the potential to serve as a major tool in bringing stability in the region by allocating the water optimally.