The offertory (from Medieval Latin offertorium and Late Latin offerre) is the part of a Eucharistic service when the bread and wine for use in the service are ceremonially placed on the altar.

A collection of alms (offerings) from the congregation, which may take place also at non-Eucharistic services, often coincides with this ceremony.

The Eucharistic theology may vary among those Christian denominations that have a liturgical offertory.

In the Roman Rite, the term "Preparation of the Gifts" is used in addition to the term "Offertory" (both capitalized) or, rather, the term "Preparation of the Gifts" is used for the action of the priest, while the term "Offertory" is used for the section of the Mass at which this action is performed in particular when speaking of the accompanying chant.

In Baptist churches, the offertory refers to the part of the service of worship in which collection plates or baskets are distributed by ushers, with the tithes and offerings subsequently being brought to the chancel.

Offertory hymns are often sung during preparation and collection.