When Eärendil was resolved to sail to Aman to plea for help from the Valar, Aerandir along with Falathar and Erellont went with him and when they reached the shores of the Blessed Realm, he and others remained aboard while Eärendil sought the Valar. After Eärendil's embassy was complete, Eönwë, the herald of Manwë came to him and the others and set them upon another ship, and then Manwë set a great wind to blow them East back to Middle-earth.
His fate afterwards is unknown.
Aerandir is a word Sindarin for 'Sea Wanderer'.
- The Silmarillion pgs. 248 & 250