The short‐run impact of Bt cotton adoption has been well documented; however, the sustainability of the impact remains unclear. In particular, pest resistance build‐up and secondary pest outbreaks have caused concern regarding the sustainability of this benefit. This paper analyses the effects and impact dynamics of Bt cotton adoption in China. Using six unique waves of panel data collected between 1999 and 2007, we show that the benefits of Bt cotton continue 10 years after it has been commercialised, albeit with evidence of a decline in the benefit since the early adoption period. Importantly, we also show that the benefit has been shared by both Bt and non‐Bt cotton adopters.