The song was written and produced by Jackson and Jimmy Jam and Terry Lewis, with Melanie Andrews serving as co-writer.

The song received generally favorable reviews from music critics, who praised the track's sweetness and Jackson's tender delivery.

It was also praised for its meaningful message, considered to be a teaching tool to encourage sexual abstinence amidst the AIDS crisis at the time.

A music video for "Let's Wait Awhile," directed by Dominic Sena, co-stars martial artist and actor Taimak, and tells the story of a couple in love.

According to the song's producer Jermaine Dupri, "With U" takes place after the act of intimacy the two have put off, which results in "romantic confusion".

[8] "Let's Wait Awhile" is written in the key of C♯ major, set in a rock ballad tempo of 87 beats per minute.

Ed Hogan of AllMusic saw the song as a "sweet, soft departure from the hard funky veneer of [previous singles] 'What Have You Done for Me Lately,' 'Nasty,' and 'Control.

'"[3] Eric Henderson of Slant Magazine praised "how perfect her tremulous hesitance fits into the abstinence anthem 'Let's Wait Awhile'," also noting that it "would've been a great place to end the album.

"[13] Danyel Smith of Vibe praised the track, writing that "on the fragile [ballad], Jackson's tender, hesitant delivery conveys all of the trepidation and wonder felt by a young girl on the brink of losing her innocence.

"[14] Wendy Robinson of PopMatters praised the track for "showcas[ing] Janet's ability to combine a gorgeous melody with a meaningful message.

"[15] Nick Levine wrote for Digital Spy that the "seemingly gooey '80s ballad has a hard centre," referring to the song's lyrics.

Beckley eventually reached an out-of-court settlement with Jackson and her co-writers Jimmy Jam and Terry Lewis, thus preempting litigation for plagiarism.

[17] In the United States, "Let's Wait Awhile" peaked at number two on the Billboard Hot 100, behind Club Nouveau's "Lean on Me."

[30] For the performance of "Let's Wait Awhile" on the All for You Tour in 2001 and 2002, Denise Sheppard from Rolling Stone called the number "mellow," and commented, "Without question, one of the night's most beautiful and verklempt moments arrived out of nowhere forty-five minutes into the set.

It was the first time that a break in the action occurred—no dancers, no music—and as a close-up captured Jackson looking genuinely happy, the audience spontaneously burst into what became a five-minute standing ovation.

'"[31] The February 16, 2002 final date of the tour at Aloha Stadium in Hawaii was broadcast by HBO, and included a performance of the song.

[33] In contrast, Marsha Lederman of The Globe and Mail perceived that the performance was "a bit bumpy, and she seemed to be struggling a tad as she held her hand up to her ear in an effort to catch the right notes.

"[34] On the Number Ones: Up Close and Personal tour, Jackson used a diamond-encrusted lavender gown to perform a ballad medley of "Nothing," "Come Back to Me," and "Let's Wait Awhile.

"[36] Joanna Chaundy of The Independent agreed, calling it "the highlight of the show's first half since her voice was more audible and still in fine form.

"[37] The song was also included in Jackson's 2015-2016 Unbreakable World Tour; writing for the Hartford Courant, Thomas Kintner pointed out that the performance showcased "that even though singing is not the most evocative part of her repertoire, it generates smallish vocal flourishes to augment her pleasant baseline tone.