The former Friends star, who turns 50 today, rung in her half century a little early with a star-studded bash at upscale Sunset Tower on Sunset Boulevard on Saturday, February 9.
Jen was surrounded by a legion of family, friends and colleagues with an elite guest list to rival the world's biggest award shows.
A surprise show was ex-husband Brad Pitt, confirming more than a decade of rumours that the pair remained close friends following the break down of their marriage in 2005.
And proving she stays amicable with more than one former flame Jen's ex-boyfriend John Mayer was also on hand to wish her well.
Another ex of Mayer's, singer Katy Perry, arrived on a motorcycle with her current love Orlando Bloom.
Other famous faces were Jen's former co-stars Courteney Cox and Lisa Kudrow, as well as industry heavyweights Kate Hudson, Reese Witherspoon, Robert Downey Jr, Ellen DeGeneres and the Clooneys.
No Hollywood party is complete without a photo booth to capture memories of the big night, and judging by social media Jen's pals made great use of the facility at the Sunset hotel.
Fashion journalist and CNN style host Derek Blasberg took to Instagram to share a series of shots with his 828,000 followers.
The photos showed a smiling Jen at the centre of a group which included Gwyneth Paltrow, Orlando Bloom, Katy Perry and Courteney Cox.
Blasberg's partner and fellow fashion industry buff Nick Brown shared a similar collage from the gathering.
Jen Meyer, a jewellery designer and close pal of Jen's, also shared a series of shots on social media.
The collection shows Aniston, Meyer, Sara Foster, makeup artist Gucci Westman and another unidentified woman posing up a storm and playfully blowing kisses at the camera.