Song written by Pete Lee, Steve Nesfield, Gavin O'Malley, Chris Billam, Kim and Ricky Wilde, and recorded by Kim Wilde and Lawnmower Deth and released in December 2017. Kim joined Lawnmower Deth on stage during Download festival in 2016. Shortly afterwards, the collaboration on a new track was suggested. Pete Lee, vocalist for Lawnmower Deth, said the collaboration was "the greatest project [the band has] been involved in". The song has been described as an "anti-Christmas song" and a "punk and thrash-metal crossover number with thrashing riffs and hardcore vocals".
The single was released on 15 December 2017 as a digital download. Physical CD-singles were made for promotional purposes only, and being sold during a concert in Manchester on 22 December 2017 and some Kim Wilde concerts during 2018.
There are two versions of 'F U Kristmas': the clean version and the sweary version.
Kim and Lawnmower Deth performed the song live once, in Manchester on 22 December 2017.