In 1926, Pope Pius XI established World Mission Sunday for the universal Church, and the first worldwide collection took place the following year, in October 1927. The theme for World Mission Day 2026 is “One in Christ, united in mission.” The celebration this year will mark the 100th anniversary of the day’s establishment. World Mission Sunday invites Catholics everywhere to recognize our shared responsibility for the evangelization of the world and to express our unity through prayer and generosity.

According to the Pontifical Mission Societies USA in 2025, funds collected on World Mission Sunday have supported 82,498 seminarians in formation; 258,540 religious sisters providing care and catechesis; and 844,000 catechists sharing the faith at the grassroots. The funds have also helped sustain 12,000 health care centers; 8,750 orphanages and homes for the elderly, and have helped with the construction of 570 new churches.