The productivity of wheat is highly vulnerable to climate change. Optimizing the sowing period of a crop may be one of the most important climate resilient strategies to optimize yield. First, the CERES-Wheat model was used to analyze effects of climate change on the optimum sowing window of wheat. Second, it was used to determine the optimum sowing window for different zones within Punjab state, India. The simulation results suggested that climate change has caused a shift in the optimum sowing window of wheat. The current (2006–2015 weather data) optimum sowing window is 22–28 October in north eastern Punjab, 24–30 October in central Punjab, and 21–27 October in south western Punjab. The rate of decrease in productivity with delay in sowing from the optimum sowing window by each day was lowest for north eastern Punjab (36.09 kg ha−1 day−1) and highest for south western Punjab (70.80 kg ha−1 day−1). The methodology followed in this study can be useful in determining the optimum sowing time of various crops.