In the United States, the single became Harris' twelfth and Smith's first number-one on Billboard's Dance/Mix Show Airplay Chart in its 6 October 2018 issue.

"[9] The announcement was accompanied by a Japanese-inspired retro single artwork, which depicts a lone tree rising up in front of the ocean against a faded pink backdrop.

[13][14][15][16] On 15 August, Smith posted a promotional photo on Twitter ahead of the single's release, showing them and Harris relaxing on a rooftop while sharing a bottle of wine and a pizza.

[21] Brandy Robidoux of Hollywood Life called the song "a music match made in heaven", writing that Smith's "smooth vocals" provides a "soulful vibe", while retaining the "classic Calvin thumping beat".

[22] The music video for "Promises" was released on 4 September, directed by Emil Nava, and it honors the LGBT community with references to the ball scene and voguing.