In the year 2965, Erestor agreed to be a member of the Original Fellowship, the goal of which was to assist Bingo Bolger-Baggins in his quest to destory the One Ring. The mission failed, however, when Bingo's will was overpowered by that of the Ring and he was forced to turn back.
Erestor attended the Council of Elrond on October 25, 3018. During the discussion about what to do with the One Ring, Erestor asked whether Tom Bombadil could be called upon to help, or whether the Ring could be sent to him for safe-keeping, but that option was rejected. When it seemed clear that destroying the Ring was the only option, Erestor said, "That is the path of despair. Of folly I would say, if the long wisdom of Elrond did not forbid me." But Gandalf replied, "Let folly be our cloak, a veil before the eyes of the Enemy!" After the War of the Ring, Erestor was among the party that accompanied Arwen to Minas Tirith for her wedding to Aragorn. They arrived in the city on Midsummer's Eve of 3019. It is not known whether Erestor left Middle-earth with Elrond in September of 3021, but it is likely that he passed over the sea into the West at some point.