Since the term “blue carbon” was coined by the report of Nellerman et al. (2009) the marine carbon cycle has firmly entered the realm of marine policy alongside its terrestrial neighbour, “green carbon” (Crooks et al., 2018). Many marine policy decisions rely on accurate information concerning the stocks of blue carbon in a region, the annual sequestration rates associated with those stocks and the threats posed to those stocks by human activities, and especially recently by bottom-trawling (e.g., Sala et al., 2021). Hence policy officials are reliant on accurate blue carbon scientific advice. However, at the present moment there is one topic that is contributing confusion to policy-science understanding, and that is the topic of organic vs. inorganic carbon. The aim of this short note is to clarify the differences between these two types of blue carbon and to recommend how they are treated in policy formulation and the provision of scientific advice.