The earliest European epoch and substage of the Early Cretaceous epoch, preceded by the Tithonian and followed by the Barremian stage. It is dated at 145.5–130 Ma ago (Int. Commission on Stratigraphy, 2004) and comprises the Berriasian, Valanginian, and Hauterivian ages. Some authors restrict their use of Neocomian to just the Berriasian and Valanginian, whilst others extend it to include the Barremian and Aptian.