We examine the U.S. internal migration response to increased import competition following the granting of Permanent Normal Trade Relations to China in 2001. Using a variety of data sets and empirical approaches, we find that local labor markets most exposed to the policy change experienced a relative reduction in population growth over the following decade. The majority of the effect occurs at a lag of seven to ten years and is most pronounced among young individuals and low-education groups. Such population adjustments should influence the interpretation of evidence in the growing literature on import competition and local labor markets.