The emerging deep-sea mining industry faces an opportunity for tremendous economic gain through the commercial harvest of a variety of high-grade minerals found at great ocean depths around the world. A certain negative consequence of mining, and thus a potential flashpoint for social conflict, lies in the damage to deep-sea ecosystems that will result from these activities. To advance the conversation on managing the economic consequences of currently unknown environmental impacts of deep-sea mining, we develop a typology of potential environmental impacts. We draw on the literature from similar industries to show how others have implemented financial tools – specifically, environmental bonds, environmental insurance, and mutual insurance – to deal with each type of impact. We argue that proper planning is needed to specify and identify the most appropriate mechanism, or combination thereof, that provides adequate financial protection against unknown environmental impacts related to deep-sea mining.