Written by Lily, Brian Higgins, Matt Gray, Miranda Cooper, Wayne Hector and Annie Yuil, and produced by Xenomania, It was released on 21 April 2013 and debuted at number 40 on the UK Singles Chart.

On 21 February 2013, Lily announced on Twitter that "Party Over" is to be released as her third single, She unveiled a 20-second teaser clip of the song on her official SoundCloud page.

Lily revealed during an interview that she heard the chorus of the track being made in the studio, ran upstairs into the guy's office and said she wanted to sing on it.

4Music wrote a review stating that Lily sound "almost Rihanna-like in parts of the verses" and continued to praise her "powerful voice" which "belts out the words and proves that the party is far from over.

"[5] From Digital Spy, Robert Copsey gave the track 3 out of 5 stars, which is a positive review, stating that "is certainly quirky, but it feels too soon to fully commit just yet.

Eve Barlow from NME wrote a negative review of the song saying that "it's the production team [Xenomania]'s worst work to date".