The 'Fosse/Verdon' star pulled out all the stops for Sunday's awards show.
The BFFs stepped out to the annual awards show at the Microsoft Theater in Los Angeles on Sunday, posing for pics separately and together.
Williams wowed in a strapless embroidered Louis Vuitton gown, sporting platinum blonde hair and minimal jewelry.
Meanwhile, Philipps opted for a light yellow dress, still rockin' pastel pink hair.
Williams has yet to win an Emmy, but later tonight, that might just happen! The blonde beauty (who split from Phil Elverum earlier this year after less than one year of marriage) is nominated for Outstanding Lead Actress in a Limited Series or TV Movie for her portrayal of Gwen Verdon in FX's Fosse/Verdon, and brought along Philipps as her date for support.
Speaking with ET earlier this year, Williams said transforming into the multi-talented dancer/choreographer/singer was a challenge. "It's a lot," she confessed. "I mean, you start researching as soon as you get the part. There's like one good moment when you get the job and then the panic sets in and you go to work."
"It was pretty much, like, the longest job of my life," she added. "We just wrapped [filming] a couple of weeks ago, and we started in August. It was physical in not just the dancing, but in aging and figuring out how to physically change somebody from 29 up to 64 -- figuring out how that would affect their body."
Hear more in the video below, a click through the slideshow for more stylish looks from the Emmys red carpet.