Year 425 BC was a year of the pre-Julian Roman calendar. At the time, it was known as the Year of the Tribunate of Atratinus, Medullinus, Cincinnatus and Barbatus (or, less frequently, year 329 Ab urbe condita). The denomination 425 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.