The disclosure provides integrated circuit (IC) structures with single diffusion break (SDB) abutting end isolation regions, and methods of forming the same. An IC structure may include: a plurality of fins positioned on a substrate; a plurality of gate structures each positioned on the plurality of fins and extending transversely across the plurality of fins; an insulator region positioned on the plurality of fins and laterally between the plurality of gate structures; at least one single diffusion break (SDB) positioned within the insulator region and one of the plurality of fins, the at least one SDB region extending from an upper surface of the substrate to an upper surface of the insulator region; and an end isolation region abutting a lateral end of the at least one SDB along a length of the plurality of gate structures, the end isolation region extending substantially in parallel with the plurality of fins.