Seed companies have developed novel weed control technologies to combat herbicide-resistant (HR) weeds based on the use of new genetically-modified (GM) crop cultivars and auxin herbicide formulations. These herbicides can variably affect the growth and yield of susceptible cotton even at low concentrations depending on growth stage at exposure. As such, research was conducted in each of two locations in Mississippi in 2014, 2015, and 2016 to determine the cotton growth stage most susceptible to injury and yield effects from simulated misapplications of sub-lethal 2,4-D or dicamba concentrations. Results indicate that generally a decrease in yield partitioned on lower nodes and inner positions was accompanied by a compensatory increase in yield partitioned on vegetative branches and aborted terminals. However, the magnitude of these yield effects differed based on growth stage at exposure and based on which herbicide was used.