Open communion is the practice of Christian churches that allow individuals other than members of that church to receive Holy Communion (also called the Eucharist or the Lord's Supper). The phrasing and exact requirements in a particular local church may vary, but membership in a particular Christian community is not required.

Open communion is the opposite of closed communion, where the sacrament is reserved for members of the particular church or others with which it is in a relationship of full communion or fellowship, or has otherwise recognized for that purpose. Closed communion may refer to either a particular denomination or an individual congregation serving Communion only to its own members.

In the United Methodist Church, open communion is referred to as the Open Table.

Generally, churches that offer open communion to other Christians do not require an explicit affirmation of Christianity from the communicant before distributing the elements; the act of receiving is an implicit affirmation. Some churches make an announcement before communion begins such as "We invite all who have professed a faith in Christ to join us at the table."