Summertime is a single released by R&B singer Beyoncé featuring rapper P. Diddy in 2003. The song was the second and final single released to promote the movie The Fighting Temptations, in which Knowles plays the leading lady. The song is not featured in the movie but is part of the official soundtrack. It first appeared as a B-side to Knowles' 2003 smash hit "Crazy in love".

As it was released just seven days after the third single from Knowles' Dangerously in Love, "Me, Myself and I", the song did not become a big hit and an official music video was never shot for it. The song however was part of the set list on Knowles' Dangerously in Love World Tour.