Gate-all-around integrated circuit structures including varactors are described. For example, an integrated circuit structure includes a varactor structure on a semiconductor substrate. The varactor structure includes a plurality of discrete vertical arrangements of horizontal nanowires. A plurality of gate stacks is over and surrounding corresponding ones of the plurality of discrete vertical arrangements of horizontal nanowires. The integrated circuit structure also includes a tap structure adjacent to the varactor structure on the semiconductor substrate. The tap structure includes a plurality of merged vertical arrangements of horizontal nanowires. A plurality of semiconductor structures is over and surrounding corresponding ones of the plurality of merged vertical arrangements of horizontal nanowires.