Assessing the impacts of climate change on cotton is essential for maintaining a stable fibre production in the future. Here, cotton plants (Gossypium hirsutum L.) were raised under two temperature regimes (28/18 oC and 32/22 oC) and their corresponding nocturnal warming (+4oC) scenarios (i.e. 28/22 oC and 32/26 oC), and subsequently exposed to two water (Well-watered and Water deficit) and heatwave treatments (Control and Heatwave). Warmer day growth temperatures increased growth rate and leaf carbon gain, but decreased aboveground biomass. Water treatment independently or interactive affected leaf physiology and yield with growth temperature, but these impacts were generally small. Nocturnal warming did not strongly alter leaf carbon balance and its impacts on biomass were thermal regime specific. Warm temperature preconditioning did not ameliorate the negative effects of heatwave on carbon gain, but biomass accumulation was less affected due to high resilience. Overall, both short- and long-term elevated daytime temperature decrease cotton yield, while nocturnal warming has limited capacity to buffer that impact. Moderate water deficit will not strongly reduce carbon gain and growth. Findings of this study improve the knowledge regarding the response of cotton plants to climate change and underscore the complexity of plant response to multiple environmental factors.