Couplings for implanted leads and external stimulators, and associated systems and methods are disclosed. A system in accordance with a particular embodiment includes a cable assembly that in turn includes an electrical cable having a proximal end and a distal end. A first connector is attached to the cable toward the proximal end and has a plurality of first connector contacts positioned to releasably connect to an external patient device. A second connector is attached by the cable toward the distal end, and includes a first portion and a second portion pivotably connected to the first portion. The first portion has a slot elongated along a slot axis and positioned to receive an implantable patient signal delivery element axially along the slot axis. The second portion has a plurality of second connector contacts positioned to releasably, electrically contact the signal delivery element when the signal delivery element is positioned within the slot and the first and second portions are placed in a secured position. At least one of the first and second portions is pivotable relative to the other between the secured position and an unsecured position.