In Christian churches, open communion is the practice of serving of the elements of communion (also called Eucharist, The Lord's Supper) to any who can affirm that they are a Christian. The phrasing and exact requirements of a particular local church can vary, but in contrast to closed communion, membership in a particular Christian community is not required. See also intercommunion.

Most Protestant churches practice open communion. Notable exceptions include the Lutheran Church - Missouri Synod and some Reformed tradition churches.