Satan will end in the Lake of Fire for all eternity - Revelation 20:7-10

And when the thousand years are expired, Satan shall be loosed out of his prison, And shall go out to deceive the nations which are in the four quarters of the earth, Gog and Magog, to gather them together to battle: the number of whom is as the sand of the sea. And they went up on the breadth of the earth, and compassed the camp of the saints about, and the beloved city: and fire came down from God out of heaven, and devoured them. And the devil that deceived them was cast into the lake of fire and brimstone, where the beast and the false prophet are, and shall be tormented day and night for ever and ever.

After the end of Jesus reign of one thousand years, Satan will be released from the bottomless pit and he will go out to the four corners of the earth in order to deceive the nations. After recruiting an army of ungodly rebels, the Devil will march toward Jerusalem, but fire will come down from God, out of heaven, and consume the troops. After the destruction of the army that Satan gathered, he will be cast into the lake of fire to be tormented for eternity.