The data set comprises radiocarbon (14C) ages obtained on three sediment cores (Co1010, Co1305 and PS81/283) and additional information on the sample preparation of compound-specific 14C ages and carbonates. 14C ages were measured on different fractions of organic and inorganic carbon extracted from the sediments: bulk organic carbon (bulk OC), carbonates (foraminifers and mollusc shell debris) and fatty acids of different chain lengths (FA). The ages are presented and discussed in Berg et al. in review (Compound-specific radiocarbon analysis of (Sub-)Antarctic coastal marine sediments - potential and challenges for chronologies)