Three-way connectors are pipe fittings and pipeline connectors. Also known as three-way pipe fittings or three-way connectors, they are used where the main pipeline needs to branch off.

A three-way is a chemical pipeline fitting with three openings: one inlet and two outlets; or two inlets and one outlet. It comes in T and Y shapes, with both equal and unequal diameter openings, and is used at the junctions of three identical or different pipelines. The primary function of a three-way is to alter the direction of the fluid.