"Upgrade U" is a song by American singer and songwriter Beyoncé from her second studio album B'Day (2006). The song features additional vocals from American rapper Jay-Z. It was composed by Swizz Beatz, Cameron Wallace, Beyoncé, MK, Makeba, Sean Garrett, Angela Beyincé, Jay-Z, Willie Clarke, Clarence Reid, and Beyoncé's sister, Solange. Columbia Records released "Upgrade U" as a promotional single on October 8, 2006 in the United States only. "Upgrade U" draws from the genres of hip hop and contemporary R&B. The concept of the song is that of a woman describing herself as the key to upgrading a man's lifestyle.

"Upgrade U" was generally well received by music critics, some praising Beyoncé's assertiveness while singing about her ability to improve her man's life (to one of extravagant luxury) with her presence. Many also praised the natural chemistry that Beyoncé and Jay-Z have in the song. After the release of B'Day, "Upgrade U" started to gain popularity on R&B and hip hop radio stations in the United States. This prompted its pre-release debut on the US Hot R&B/Hip-Hop Songs chart and later on the US Billboard Hot 100 chart; after its promotional release, the song peaked at number 11 and at number 59 on the Hot R&B/Hip-Hop Songs and the Hot 100 charts respectively.

The music video for the song was directed by Melina Matsoukas, and took one and a half days of shooting. Beyoncé did an impersonation of Jay-Z in the clip and is also seen amidst gold watches and jewelry, continuing the motif of luxury that is alluded to in the song. It finally emerged as the forty-fifth best R&B/Hip-Hop song of 2007 in the United States. Although Beyoncé did not perform "Upgrade U" in any televised appearances, the song was a part of her set list on The Beyoncé Experience tour (2007), and I Am... World Tour (2009–10), as well as her and Jay Z's joint On the Run (2014) and On the Run II (2018) all-stadium tours.