Abstract Despite high expectations about the role of carbon removal in meeting global climate targets, many of the proposed techniques remain nascent. This is especially so for techniques with potential for large-scale, permanent removal of CO2, such as direct air carbon capture and storage (DACCS) and ocean alkalinity enhancement (OAE). In such a context, understanding public attitudes is crucial but challenging, since we do not have enough information about the sociotechnical configurations which might accompany such proposals over future timescales. Carbon removal at scale will not take place in a vacuum—it will co-evolve within political, social, economic, and legal structures which in turn will have a strong influence on public attitudes. This study used a nationally-representative survey (n = 1978) in the UK to test the impact of alternative sociotechnical systems on public attitudes to DACCS and OAE. Participants were randomly assigned to one of five scenario conditions, representing different forms of governance logic (top–down vs bottom–up) and market logic (planned vs liberal economy), plus one with minimal sociotechnical information. We find that the scenario condition significantly impacted perceptions of OAE, with participants preferring its implementation within a bottom–up, planned economy scenario, and rejecting scenarios which most closely resembled the status quo. There were no significant differences between scenarios for DACCS, suggesting that the technology may be more flexible across alternative sociotechnical arrangements. OAE arouses more negative emotions, particularly worry about impacts on ocean ecosystems, whereas DACCS arouses more hope. We found that climate worry is associated with stronger emotions—both positive and negative—toward both techniques, thus carbon dioxide removal (CDR) could be polarising for the most climate-worried, likely due to tensions between climate urgency and concerns about deterring emissions reductions. The most important criteria for future CDR deployment were deemed to be biodiversity, durability, and cost, with a strong discourse around the current cost-of-living crisis.