Background and release
The single artwork was leaked online on October 8, 2016. Little Mix officially announced the single title and artwork on the October 9, 2016 via Twitter and Instagram - also announcing that they will be performing the song live on the X-Factor, releasing the song instantly after.   Tabloid paper, The Sun, released a story the following day leaking some of the songs' more suggestive lyrics. At the time they were unconfirmed, however an indirect tweet from the girls confirmed that they were real. On the October 11, 2016 Little Mix released a 15 second snippet of the song and music video via their Twitter account. 
Celebmix writer Annemarie stated: "The music behind Shout Out To My Ex is very much pop-driven. The chorus is powerful, upbeat, and guaranteed to stick in your head for the whole day. The verses boast fresh, snappy, production that compliments the accompanying lyrics quite well." 
The song debuted at #1 on the UK Singles Chart, earning the group their fourth #1 single on the chart.  It peaked at #4 on the Australian charts as well as #1 on both the Irish Singles Chart and Scottish Singles Charts and #7 on the New Zealand Single Top 100. It also debuted at #69 on the US Billboard Hot 100 Singles chart as well as #30 on the US Digital Songs chart.
During the announcement of the song it was confirmed that the video was shot in Spain. Four teasers were released on the group's social media accounts. It was released on October 21, 2016. The music video was directed by Sarah Chatfield. It features the girls hanging out by a trailer before driving around the desert, with purple trees shown in the background. They are also shown hanging around a pool, posing and taking selfies. They later drive past a guy (Jesus Palacio) who is looking for a ride, with the girls waving in his direction but they decide to drive straight past him, leaving him annoyed. Eventually they are posing near old buildings and dancing together in the desert. The video ends with them walking together, hand in hand away from the camera.