The 26-year-old will release the Autumn Rowe-written track as the lead single from her third album, which the 'Happy' singer had previously hinted would be released later in the year.
"So excited to let u know to tune into Scott Mills show on Radio One tomorrow for the worldwide exclusive play of my summer single 'Collide' (sic)" Lewis told followers on Twitter.
Rowe - who wrote Alexis Jordan's 'Good Girl' and Cher Lloyd's 'Swagger Jagger' - tweeted: "#Collide Leona sounds AMAZINGGGGGGGGGG."
The song has been produced by Sandy Vee, whose previous work includes David Guetta's 'Where Them Girls At', Rihanna's 'Only Girl (In the World)', Alexis Jordan's 'Good Girl' and Nicole Scherzinger's new single 'Wet'.
Lewis recently described her third LP as "energetic, deep [and] unique", revealing that her biggest influences were Tears for Fears, Kate Bush and Tracy Chapman.
'Collide' will receive its first play on Scott Mills's BBC Radio 1 show tomorrow from 4.30pm. A release date is still to be confirmed.
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Watch Leona Lewis perform her 'Better In Time'/'Man Down' mash-up from Radio 1's Live Lounge below: