The Hollywood couple, which became engaged in 2012, will apparently exchange vows at San Jose del Cabo's Flora Farm in Aniston's favourite vacation spot, Cabo San Lucas, as the sun sets on Jul 26, reported Contactmusic.
Just 50 of Aniston and Theroux's closest friends and family, including celebrity friends Courteney Cox, Chelsea Handler, Sheryl Crow, Ben Stiller, Toby Maguire and comedian Jimmy Kimmel will be in attendance for the destination wedding.
"Jen wants this wedding to be casual. She wants her guests to feel as though they can kick their shoes off and join in on the dance floor...
"This evening for her will be all about making memories with those she loves the most. That's what's important to Jen now," a source said.
The nuptials will be Theroux's first and Aniston's second as she was previously married to Brad Pitt.