The former `Dancing with the Stars` contestant - who is the brother of Backstreet Boys singer Nick Carter - checked out of the Betty Ford Center after successfully completing a month-long treatment programme.
He is now back in his native Florida and working on a new album.
Aaron, 23, entered the facility last month to deal with "emotional and spiritual" issues ahead of a planned re-launch of his music career.
His manager Johnny Wright said at the time: "Several months ago Aaron came to me to help him return to music and to restart his career. He has been in Orlando working on a new album and perfecting his live show and his physical body. Aaron, understanding the challenges and hard work it would take to get himself back to the top, requested to take some time before we started to heal some emotional and spiritual issues he was dealing with.
"Therefore he has chosen to enter a facility where he feels he will get the guidance and cleansing he needs that will help him on the music journey he`s about to take. He asks that everyone keep him in their prayers and that they respect his privacy at this time."
In 2008, Aaron - who has previously dated actresses Hilary Duff, Lindsay Lohan and Amanda Bynes - was arrested for investigation of marijuana possession, and in 2009 it was revealed he owed over $1 million in back taxes.