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The present study explores recycling of NiTi shape memory alloys (SMAs) using vacuum induction melting (VIM). Recycling NiTi is considered challenging due to unavoidable carbon and oxygen pick-up, which affects structural and functional properties. A 1 kg high-purity NiTi ingot was prepared from elemental Ni pellets and Ti blocks using VIM with a graphite crucible. The resulting SMA ingot underwent three additional remelting cycles. Samples for chemical, thermal and microstructural analysis were taken from the original ingot and after each remelting step. The study analyzes how different feedstocks—pure Ni and Ti versus NiTi SMAs—affect melt pool temperatures and VIM durations. It was found that the high heat of mixing during alloy formation serves as an internal heat source, contributing to shorter VIM process durations. In contrast, remelting NiTi alloys, which lacks this heat release, relies entirely on external power, which increases the process duration and thus the time available for impurity pick-up. The VIM process is analyzed using CALPHAD-based thermodynamics, combined with novel atomistic simulations using machine-learning potentials to determine thermodynamic conditions. The study assesses energy balances and contributes to a better understanding of how VIM remelting affects the microstructures and functional properties of NiTi SMAs.