"Promise" is a song by Romeo Santos, featuring Usher, from Santos' debut studio album Formula, Vol. 1 (2011). The track was co-written and produced by Rico Love. It was released as the album's second single in Latin America and the United States.

The song combines elements of bachata and R&B and peaked atop the Billboard's Latin Songs chart, becoming the second consecutive number-one song in the chart for Santos and the first for Usher. The music video for "Promise" was directed by Anthony Mandler, who previously worked with Rihanna, Jay Z and Kanye West.

After the temporary separation of the band Aventura, Romeo Santos signed a record deal with Sony Music Entertainment and recorded his debut studio album, Formula, Vol. 1, which includes most of the tracks in bachata rhythm and bilingual songs such as the lead single "You", which peaked at number-one in the Billboard Latin Songs, and "Promise", with vocals by American singer Usher. The collaboration came through because Santos' manager Johnny Marines introduced Usher to Santos. Usher was impressed by Santos ability to perform after seeing him on YouTube, saying: "This is the thing that people will remember". "Promise" was co-written and produced by Rico Love and features Usher singing on bachata rhythm for the first time. According to Carlos Quintana of About.com the song and the rest of the tracks included on Formula, Vol. 1 may be classified as Latin urban contemporary with R&B and hip hop influences. The track was named "fluttering" by Mikael Wood of Entertainment Weekly on his review of the parent album.

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