Migrants worldwide play an important role in sectors vital to addressing the COVID-19 pandemic but are also exposed to higher risks of contracting the virus. Collecting, analyzing and using data on migrants has become increasingly important in light of both of these factors, including to advocate for their inclusion in national vaccination plans to leave no one behind. Despite this, the implementation of extensive local and international mobility restrictions and reprioritization of resources have exacerbated pre-existing challenges to migration data collection. A series of surveys conducted by the World Bank and the United Nations Statistical Division showed that the pandemic hinders many data-related activities and heightens existing data inequalities. This message was echoed by migration data experts from across Europe, Asia, Africa and the Americas in the recent Migration Policy Practice outlook on human mobility in 2021. The implementation of planned censuses in the current 2020/2021 round, surveys, and other sources of data on migrants and human mobility have all been negatively affected