"Lost Without" is co-written by Kelela and Kindness, and follows on from last month's duet with Robyn, "Cry Everything".
The new single is Seinabo Sey's first new music since last year's I'm A Dream record.
Kindness hasn't released an album since 2014's Otherness.
"Lost Without" is out now. Kindness plays London's Oslo on 14 June. Find out more.