Integrated circuit structures having deep via structures, and methods of fabricating integrated circuit structures having deep via structures, are described. For example, an integrated circuit structure includes a plurality of horizontally stacked nanowires. A gate structure is over the plurality of horizontally stacked nanowires. An epitaxial source or drain structure is at an end of the plurality of horizontally stacked nanowires. A conductive trench contact structure is vertically over the epitaxial source or drain structure. A conductive via is vertically beneath and extends into the conductive trench contact structure. The conductive via has a first width beneath the epitaxial source or drain structure less than a second width laterally adjacent to the epitaxial source or drain structure.