[2] In an interview with New Zealand radio DJ Zane Lowe for the Apple Music podcast Beats 1, Paak said the song required a lot of "patience and delicate".

[5] On March 5, 2021, "Leave the Door Open" was released by Aftermath Entertainment and Atlantic Records as the album's first single via digital download and streaming services in various countries.

[10] On April 1, 2021, a live recording of the single was released for digital download and streaming, using audio from the 2021 Annual Grammy Awards performance with added narration from Collins.

[15] "Leave the Door Open" was written by Mars, Brandon Anderson, Dernst Emile II, and Christopher Brody Brown.

Harding pointed out that its modern approach can be heard at the end of Paak's first verse, to which Parx responded, "You can hear [the early influences] in his voice, but those cadences are still very contemporary.

[29][23] Variety writer Jem Aswad and Sophie Williams from NME affirmed "Leave the Door Open" resembles songs by the Delfonics, the Chi-Lites, and the O'Jays.

[34] Pareles praised the song's instrumentation, the key changes, lyrics, and the contrast between the backup and lead vocals, concluding that they were "all good things to revive".

"[36] No Ripcord's Joe Rivers called the track "outstanding ... [the] harmonies recall the best moments of The Stylistics while still leaving room for .Paak's taut drum fills".

"[37] Ross Scarano commenting on Pitchfork called "Leave the Door Open" one of the highlights of An Evening with Silk Sonic, due to its "slathering elevated technique—all those key changes—with satisfying molten cheese".

"[39] Hot Press's writer Pat Carty wrote that if the song "managed to assume human form, [it] would doubtless sport a tasteful silk shirt and medallion combo".

"[41] AllMusic's critic Andy Kellman said the track "best meshes the smooth and tender style of Mars with Paak's nephew-of-Bobby Womack rasp".

[42] Josh Glicksman commenting in the Billboard "Five Burning Questions" article said the track is "tailor-made to dance and snap along to as it gets delightfully stuck in your head".

[20] Entertainment Weekly's Eli Enis and Alex Suskind recalled "pitch-perfect harmonies" of "Leave the Door Open", placing it on the segment "Friday Five" on March 5, 2021.

"[31] Dave Holmes, in Esquire's "Best Songs of 2021 (So Far)" praised "Leave the Door Open", calling it a "flawless tribute to mid-'70s R&B with a key change that will make you stand up and cheer".

"[46] The song was considered the best release until June 2021 by Complex; Jessica McKinney wrote "rarely does a new record come along that can bring together all generations, but 'Leave the Door Open' does exactly that.

Carl Lamarre affirmed Silk Sonic "recreated the lush sounds of '70s soul, but with enough modern finesse to still conquer audiences not even born until decades later".

The song reached top spot in its sixth week, matching the previous record held by Ed Sheeran's "Shape of You" (2017).

[96][97] "Leave the Door Open" entered the top twenty of the Argentina Hot 100 and peaked at number one on Billboard Mexico Airplay.

[113] The music video for "Leave the Door Open" premiered alongside the song's release on March 5, 2021, and was directed by Mars and Florent Dechard.

[115][28][116] Silk Sonic and the band wore "sunglasses and vintage printed shirts" as they perform the song, with close-up shots of Mars and Paak.

[120] The Recording Academy interim president/CEO Harvey Mason Jr. confessed their performance was intentionally not announced to create "buzz", while there was also some uncertainty regarding it.

[122] Silk Sonic made their performance debut at the 63rd Annual Grammy Awards on March 14, 2021, adopting a 70s aesthetic accompanied only by two backup singers.

[123][124] The show featured a "retro flare" similar to the Music Video; Mars, Paak and the back up singers wore three-piece "burnt orange leisure" suits with "wide-collared polyester shirts, bell-bottoms" and "bootcut pants".

Eric Todiso from People said that Silk Sonic "stole the show at the 2021 Grammy Awards", dubbing the performance "dazzling and dreamy".

[121] Entertainment Weekly's staff considered the performance to be one of the most memorable moments of the show, reminiscent of the "glooses '70s style as a Soul Train telecast".

[130] Joe Lynch from Billboard, Randall Roberts from the Los Angeles Times, and MTV News's Hosken all regarded the performance as inspired by the 1970s Soul Train.

[132] Silk Sonic was joined by two back-up vocalists, all dressed in "dark azure crushed velvet blazers", "with roses attached to the lapels" and tinted sunglasses as Paak wore a flat cap.

[139] Lynch from Billboard praised the duo's performance as they "worked the crowd exactly like the '70s soul singers that Silk Sonic pays homage to would have".

[143] Rolling Stone's Brittany Spanos declared that Silk Sonic transformed the 2021 BET Awards "into a smokey lounge with [their] velvety performance.

"[149] The parody then proceeded to show Corden and the band, dressed in '70s inspired clothes, as they sang in a "yellow-walled studio" similar to the set of All in the Family (1971–1979).