For nearly forty years, National Migration Week (NMW) has been celebrated the week after the Epiphany in January. One of the primary reasons for the selection of these dates was due to the timing of the Pope's Migration Day message, which was celebrated in mid-January.
In 2019, Pope Francis announced that that the World Day of Migrants and Refugees would henceforth be celebrated on the last Sunday of September. To maintain the custom of aligning NMW with the World Day of Migrants and Refugees, the Catholic Bishops of the United States recently decided to move National Migration Week to the last week in September.