Flat chain is a form of chain used chiefly in agricultural machinery. Early machinery made extensive use of flat chain. It has been gradually replaced in most applications by roller chain, which is quieter, lasts longer, and requires less frequent retensioning.

Modern flat chain is made from stamped steel. Individual links can be put together or taken apart using simple tools, unlike roller chain which requires a master link or special splicing equipment.

Today, flat chain is used most often for conveyers, because it lends itself well to the attachment of slats, flights, buckets, and prongs used to move material. Such attachments can be welded on in the field, or can be purchased ready-made on a single link (or pair of links where the conveyer uses two chains) and then spliced into a loop of chain.

Older forms of flat chain were made of iron. Though the sprockets are compatible with modern chain, the two types cannot be spliced together.

One type of tool used to splice flat chain is called a religion saver.