Changes in atmospheric [CO2], temperature and precipitation under projected climate change scenarios may have significant impacts on the physiology and yield of cotton. Understanding the implications of integrated environmental impacts on cotton is critical for developing cotton systems that are resilient to stresses induced by climate change. The objective of this study was to quantify the physiological and growth capacity of two cotton cultivars under current and future climate regimes. This experiment compared the early-season growth and physiological response of an older (DP16, released in the 1970s) and a modern (Sicot 71BRF, released in 2008) cotton cultivar grown in ambient and elevated atmospheric [CO2] (CA, 400µLL-1 and CE, 640µLL-1 respectively) and two temperature (TA, 28/17°C and TE, 32/21°C, day/night, respectively) treatments under well-watered conditions. CE increased biomass and photosynthetic rates compared with CA, and TE increased plant biomass. Although limited by the comparison of one older and one modern cultivar, our results suggest that substantial potential may exist to increase breeding selection of cotton cultivars that are responsive to both TE and CE.