Embodiments of the present invention provide an apparatus and method for wafer thinning endpoint detection. Embodiments of the present invention utilize through silicon via (TSV) structures formed in the wafer. A specially made wafer handle is bonded to the wafer. Conductive slurry is used in the wafer backside thinning process. The wafer handle provides electrical connectivity to an electrical measurement tool, and conductive posts in the wafer handle are proximal to a test structure on the wafer. A plurality of electrically isolated TSVs is monitored via the electrical measurement tool. When the TSVs are exposed on the backside as a result of thinning, the conductive slurry shorts the electrically isolated TSVs, changing the electrical properties of the plurality of TSVs. The change in electrical properties is detected and used to trigger termination of the wafer backside thinning process.