Fluid conduits for plumbing and other uses having integral end fittings are disclosed herein. A method of forming a fluid conduit in accordance with an embodiment of the disclosure includes providing a copper tube having a first inner diameter and a first wall thickness, and heat treating an end portion of the copper tube to a predetermined hardness. The method can further include increasing the wall thickness of the end portion from the first wall thickness to a second wall thickness, and increasing the inner diameter of the end portion from the first inner diameter to a second inner diameter. The method further includes forming a circular groove in an interior surface of the end portion and positioning a seal in the circular groove.