Semiconductor packages including magnetic core inductor (MCI) structures for integrated voltage regulators are described. In an example, a semiconductor package includes a package substrate and a semiconductor die coupled to a first surface of the package substrate. The semiconductor die has a first plurality of metal-insulator-metal (MIM) capacitor layers thereon. The semiconductor package also includes a magnetic core inductor (MCI) die coupled to a second surface of the package substrate. The MCI die includes one or more slotted inductors and has a second plurality of MIM capacitor layers thereon.