The Welsh Rugby Union launched a bid to stage the showpiece event after the French Rugby Federation (FFR) withdrew Paris as the host city due to uncertainty over the availability of the Stade de France.
It means Cardiff will stage the fixture for the seventh time since the tournament's inception in 1996.
ERC also confirmed the final of the second-tier Amlin Challenge Cup will be played at the Arms Park home of Cardiff Blues.
The Blues moved back to the Arms Park from Cardiff City Stadium last season, and are currently installing an artificial pitch at the ground after struggling with a boggy playing surface.
- Sports & Recreation
- Cardiff Blues