Mennonites practice two ordinances: believer's baptism and the Lord's Supper. Baptism is administered to adults (or older youth) who make a voluntary confession of faith and a commitment to the congregation. It can be by sprinkling, pouring, or immersion — the mode is secondary; the voluntary, adult commitment is primary. Infant baptism is rejected as contradicting the voluntary nature of faith and community membership.

The Lord's Supper is observed as a memorial and a sign of community solidarity. It expresses the unity of the body of Christ and the shared commitment to the way of the cross. Many Mennonite communities also practice foot washing as an ordinance of humility (John 13), reflecting Jesus's servant example. These practices are central to communal identity but are not understood as channels of saving grace in a sacramental sense.