It was written by Johntá Austin, Jackson, Jermaine Dupri, Manuel Seal Jr., James Harris III, and Terry Lewis, with production handled by the latter five.

"With U" was considered a follow-up to Jackson's single "Let's Wait Awhile" (1986), in which two characters postpone intimacy.

The song received positive reviews from most music critics, being called "smooth and lushly".

[1] Jackson further commented about working with Dupri, Lewis and Terry, saying: "It was really a collaborative effort, and that's what made it so nice.

[2] A mid-tempo R&B song, it was described as "the follow-up to 1986's 'Let's Wait Awhile'", where two people postpone intimacy.

"[6] Spence D. of IGN commented that the song "continues the strange intersection where Janet sounds like Michael on the verses and then gets her voice obviously treated for the choruses, dipping into the feminine whirl that she's so famous for.

"[7] Glenn Gamboa, writer for Newsday, expressed a positive reaction, calling it "a nice quiet-storm ballad.