With over seventy seven million members , the Anglican Communion is the third largest communion in the world , after the Roman Catholic Church and the Eastern Orthodox Churches . With approximately more than 80 million members world wide , the Anglican Communion is the third largest Christian communion in the world , after the Roman Catholic Church and the Eastern Orthodox Churches , though it may be eclipsed if the proposed merger of the Reformed Ecumenical Council and the World Alliance of Reformed Churches to form the World Communion of Reformed Churches is ratified , producing a communion with around 87 million members .