With people’s increasing awareness regarding the vital importance of climate change on ecosystems, the financial sector has begun to implement more robust regulations and mitigation measures to enable its transition toward a greener and more sustainable economy. This has led to the rise of climate fintech. Climate fintech represents the use of new digital technologies and solutions, such as facial recognition payment systems (FRPS), AI-driven real-time ESG monitoring, and Distributed Ledger Technology (DLT) for Carbon Credit Verification (MRV), to address urgent climate change issues, foster sustainable practices, and facilitate the industry’s shift towards a low-carbon economy. Moreover, cognitive biases have not been sufficiently explored and are largely overlooked in technology adoption studies, while this chapter aims to analyze the impact of the cognitive bias known as Fear of Missing Out (FOMO) on user acceptance of climate fintech. The theoretical approach emphasizes the substantial impact of FOMO factors on users’ propensity to accept climate fintech, hence presenting essential ramifications for the ecosystem.