Inspired by the 2001 death of singer Aaliyah, the September 11 attacks, and other events in the world and in Keys' life, the song is about "how material things don't feed the soul".

[3] In 2023 the song was reinterpreted in a classical version by Keys and Kris Bowers for Queen Charlotte: A Bridgerton Story Soundtrack, which the singer performed with a 70-piece orchestra of women of color.

[11] Matthew Singer of Time Out wrote that the song "is a reminder to live in the present, and hold the one we love close as everything is transient", finding it congruent with the inspiration at the death of Aaliyah.

[16] In the United Kingdom, "If I Ain't Got You" debuted and peaked at number eighteen on the UK Singles Chart for the week ending April 10, 2004.

[18] In September 2016, Keys appeared on The Voice as a coach, with a contestant singing the song, and it made a new entry into the R&B/Hip Hop singles charts, driving total sales up to 1.5  million units.

[20] The music video for "If I Ain't Got You", directed by Diane Martel, was filmed in Harlem, New York City, and features a cameo by rapper and actor Method Man as Keys' on-screen boyfriend.

An unofficial upload of the original video on Dailymotion, dated September 27, 2006 and clocking in at 5 minutes and 12 seconds, is the only surviving copy of the full version on any online platform currently available.