LostAlone are a British rock band from Derby, England, formed in 2005. The band consists of Steven Battelle (lead vocals, guitar), Alan Williamson (bass guitar, backing vocals), and Mark Gibson (drums, percussion, backing vocals).

LostAlone have released four studio albums: Say No to the World (2007), I'm a UFO in This City (2012) and Shapes of Screams released on 7 April 2014. Their latest album, The Warring Twenties, was released on 30 September 2022.

The band have played headline tours in the UK and mainland Europe as well as regularly supporting notable artists such as My Chemical Romance, Thirty Seconds to Mars, Enter Shikari and Paramore. They have also made appearances at festivals such as Taste of Chaos, Give it a Name, Download, Reading, T in the Park, Oxegen and Rock am Ring. They received their first major award nomination when they were nominated for "Best British Newcomer" at the Kerrang! Awards in 2007.

In late 2021, the band announced they had been invited by My Chemical Romance to join them for a set of stadium shows which took place at Stadium MK (Milton Keynes, England), Sophia Gardens Cricket Ground, Cardiff and the Eden Project, Cornwall. These landmark events commenced in May 2022 after a two-year postponement due to the COVID-19 pandemic.

The band have announced a UK mini-tour which will take place December 2022.