The emergence of separate cemeteries for disposal of the dead represents a profound shift in mortuary practice in the Late Neolithic of southeast Europe, with a new emphasis on the repeated use of a specific space distinct from, though still often close to, settlements. To help to time this shift more precisely, this paper presents 25 dates from 21 burials in the large cemetery at Cernica, in the Lower Danube valley in southern Romania, which are used to formally model the start, duration of use and end of the cemetery. A further six dates were obtained from four contexts for the nearby settlement. Careful consideration is given to the possibility of environmental and dietary offsets. The preferred model, without freshwater reservoir offsets, suggests that use of the Cernica cemetery probably began in 5355–5220 cal BC (95% probability) and ended in 5190–5080 cal BC (28% probability) or 5070–4940 (67% probability). The implications of this result are discussed, including with reference to other cemeteries of similar age in the region, the nature of social relations being projected through mortuary ritual, and the incorporation of older, Mesolithic, ways of doing things into Late Neolithic mortuary practice.