Rare Earth Elements (REEs) are essential components of modern technology and industry, leading to their increased release into the environment. This review synthesizes current knowledge on the transfer, accumulation, and fractionation of REEs in plants, with a focus on the impacts of REE-triggered stress at different organisation levels, and the underlying tolerance mechanisms. We explore the mechanisms governing REE uptake, transport, fractionation and distribution within plants and their potential hormetic and toxic effects under normal and stress conditions. This comprehensive review provides valuable insights into the complex interplay between REE accumulation, stress response, and tolerance mechanisms in plants, fostering a deeper understanding of REE phytotoxicity and the development of sustainable solutions for REE-contaminated ecosystems.