["Antipode, Volume 58, Issue 3, May 2026. ", "\nABSTRACT\nThis article examines the emergence of “green fintech,” a diverse subset of new financial technologies with expressly environmental aims. We suggest that an analysis of “green fintech” offers us a useful lens on the contradictions of green finance more generally. The paper looks at a range of examples, spanning processes of AI‐enabled investment screening, tokenization, and gamification, and draws recent debates about the Marxian category of “fictitious capital” into conversation with critical geography debates about processes of valuation in green finance. Green fintech applications reveal especially clearly how green finance relies on specific forms of fictitious capitalization. In particular, we argue that green fintech makes visible how green finance as a form of fictitious capital is reliant not just on articulating abstract, quantified valuations of nature, but also valorizing them through exchange.\n"]