While basic income (BI) has long been advocated for its social benefits, some scholars also propose it in response to the ecological crises. However, the empirical evidence to support this position is currently lacking and the concept of an ecological BI (EBI) is underdeveloped. Part one of this paper attempts to develop such a concept, arguing that an EBI should seek to reduce aggregate material throughput, improve human needs satisfaction, reduce inequalities, rebalance productive activity towards social activities in the autonomous (...) sphere, and promote societal values of cooperation and sufficiency. Part two examines how BI interventions consider the principles of an EBI in their designs and discusses what their findings infer about BI’s ecological credentials. The results find that while ecological considerations are largely absent from BI intervention designs, their findings suggest that interventions aligned with the principles of an EBI could play a role in addressing the ecological crises. (shrink)