The soon to be mum-of-two - who has her very own clothing collection with In The Style - is famous for her ultra-glam fashion sense but she went all chilled on us when she rocked up to the city bash alongside sister Sam Faiers over the weekend.
Giving us a glimpse of her pregnant tum, beautiful Billie slipped into a pair of super comfy spray on leggings which she teamed with a tight black vest top and a khaki shirt that she left unbuttoned.
Joined by two-year-old daughter Nelly, the former reality star ditched her trademark heels and popped on a pair of hi-top trainers to match her zip-adorned leather jacket.
Billie may have oozed casual vibes but she still looked a million dollars and her perfectly tousled blonde bob (which she recently took even shorter) and her flawless make-up (that flawless contour, though) meant she stood out from the rest of the guests.
Earlier this year, the TOWIE original - who was all smiles as she posed away for the paparazzi - announced her decision to take a break from the show to focus on other things.
Speaking to Reveal at her In The Style launch in August, the stunner said, "I just feel like I have to leave some time."
She continued, "I want to start a new chapter in my life and concentrate on other things, I mean, I do want another baby [Billie is now expecting, congrats!] and that's going to take more time. For me, filming isn't a huge commitment anymore so I just felt like now is the right time."
She hasn't ruled out a return, though.
"We're all on really good terms. It's open for me to return [and] if I want to go back I can, but I'll take the time out for this year for sure."
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