The loved up couple were pictured sharing a cuddle together in the swimming pool at the luxury Encore at the Wynn, located on the famous Sin City Strip.
Billi, dressed in a metallic bikini, is clutching a drink in her hand in the photograph and has admitted that she was feeling a little tipsy when it was taken!
Alongside the snap, which Billi has posted on Instagram, she said: "Vegas with my @andytcarroll #encore #tipsy."
Yoga teacher Billi flew to Vegas last week with her best girl friends and her sister before Andy joined her on Tuesday (17 June).
Most of Billi's pals have now returned to the UK, however she and Andy have stayed on in the US for some time together.
This is the third holiday together for the couple in the past month. On 16 May, Billi and Andy were pictured in Dubai before heading on to the Maldives together.
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