Aniston, 46, and Theroux, 43, tied the knot on August 5 in a secret wedding at their Bel Air mansion.
She wore a fitted, simple and classy dress, reported People magazine.
"It was very simple, but beautiful. It wasn't a white colour - it was like an off-white, cream colour. Very classy, fitted well and simple," said a source.
Reps for Versace, Gucci and Vivienne Westwood confirmed they did not design Aniston's dress for nuptials.