Embodiments of the present disclosure are directed towards techniques and configurations for interconnect structures embedded in a package assembly including a bridge. In one embodiment, a package assembly may include a package substrate, a bridge embedded in the package substrate and including a bridge substrate, and an interconnect structure including a via extending through the package substrate into a surface of the bridge substrate and configured to interface with a conductive feature disposed on or beneath the surface of the bridge substrate. The interconnect structure may be configured to route electrical signals between the conductive feature and a die mounted on the package substrate. Other embodiments may be described and/or claimed.