The former TOWIE star posted the cute photo on Sunday (18 January) - and pregnancy clearly suits her!
Alongside the smiling selfie, yoga instructor Billi wrote: "My LBD Not So Little Anymore Almost Half Way."
Fans were quick to comment on the picture, with one even speculating on the baby's sex, saying: "I think girl :)"
Another said: "Beautiful bump, I hope pregnancy is treating you kindly billi xx."
My LBD Not So Little Anymore Almost Half Way http://t.co/9FqvKR1W7V— Billi Mucklow (@BilliMucklow) January 17, 2015
On Christmas Day, Billie announced she and fiancé Andy Carroll were expecting their first baby.
They broke the news by uploading a picture of themselves on Instagram posing together with Billi wearing a Christmas jumper declaring: "Making my little pudding!"
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