The A-list trio were spotted partying at the members-only club Soho House in West Hollywood, along with Witherspoon’s husband Jim Toth and another man.
And an onlooker told Us Weekly that they appeared to be having a good catch-up.
'The girls were all having such a good time together,' said the witness. 'They were getting on really well and just laughing and conversing and enjoying one another's company. They were having a lot of fun!'
Fellow Hollywood heavyweight George Clooney - who was sat just a few tables away – also joined in the fun.
'There were occasional joint conversations between the two tables,' said the observer.