The spinoff racer will be available on Xbox 360, PS3 and PC from May 25 in the UK and May 29 across North America.
A downloadable demo will be available from May 1, allowing players to sample events in both single and multiplayer, as well as a beta of new gaming network RaceNet.
RaceNet will allow players to track their race times and rewards with other players, which will continue to "evolve" as other racing titles are released by Codemasters.
DIRT Showdown will also be the first title in the Codemasters Racing label, which covers the DiRT, GRID and Formula One franchises.
> Read our hands-on preview with DIRT Showdown
Watch the new 'Ultimate Hoonigan' trailer below: