A reggae-pop and R&B track, "Slumber Party" features brass, marimba, syncopated synths, percussion and a horn section in its instrumentation.

The video was released on November 18, and features Spears and Tinashe during a sleepover-themed masquerade party in a mansion, where they are seen in rooms filled with bubbles, smoke and flashing lights.

[9][10] On October 14, American singer Tinashe hinted on her Instagram account that she was recording vocals on a "legendary" collaboration with the caption: "Dreams are real.

"[11][12][13] Later, on October 25, Spears posted a picture of herself with Tinashe on the set of the song's music video, with the caption: "Neighbors say we're causing a commotion...", a line from "Slumber Party".

[20] During a 2022 interview on Watch What Happens Live with Andy Cohen, English singer Charli XCX revealed that she was asked to be featured on the remix of "Slumber Party", but she had to turn it down due to scheduling conflicts.

Mattman & Robin were also responsible for vocal production, alongside Mischke Butler, as well as programming, drums, percussion, snaps, handclaps, synths, guitars, bass, marimba and brass.

[29] Lewis Corner of Digital Spy compared its style to "Hotline Bling" (2015),[7] for which Gay Times's Daniel Megarry and No Ripcord's Luiza Lodder echoed.

[34] Across the song, Spears uses a "euphemism for one-night stands"[35] while invoking the "ritual of sleepovers with friends"[28] and the teenage game seven minutes in heaven.

"[7] Joe Pasmore of Attitude picked "Slumber Party" as a highlight, declaring that "while sharing Britney's nostalgic flare, [it] boast[s] modern production which brings the track firmly into 2016.

[32] Alex Macpherson of The Guardian noted that the song's "high-school metaphor would probably seem odder coming from a singer of that age; Spears sings it with self-awareness and a thorough commitment to the role-play scenario.

[28] Stephen Thomas Erlewine of AllMusic cited "Slumber Party" as a "heavy-breathing come-on that never manage[s] to seem sexy despite the flood of innuendo.

[7] Describing it as a sultry "pop take on Drake's smash hit 'Hotline Bling'", Daniel Megarry of Gay Times remarked: "if this doesn't make your libido increase, nothing will.

"[30] John Murphy of musicOMH commented on its sexual lyrics, declaring that the song "still manages to possess a slightly illicit thrill.

[40] In the United States, "Slumber Party" debuted and peaked at number 86 on the Billboard Hot 100, with its music video generating a weekly total of 3.8 million streams.

[16][50] Tinashe later shared the same photo, with the caption: "The face you make when the rumors are true and you collabed with your idol & basically your whole life is a dream so you keep it cute for Brit but inside you are wigless and dead.

"[15] During an interview with Extra's Mario Lopez, the singer commented that the music video would be a younger version of Stanley Kubrick's film Eyes Wide Shut (1999), adding: "It's a little risky.

[56] Later, she is "spotted by the master of the house, a guy with what appears to be a David Bowie-esque lightning bolt on his face", as noted by the Billboard staff.

[57] The magazine staff continued, "Tinashe appears midway through the story dressed for the slumber party, and the pair get cuddly on a couch in negligee before instigating a sexy dance sequence.

"[58] During the video, Spears "changes into a series of sexy ensembles — including black lingerie, and other puffy blue princess skirts",[56] as well as crawls across a table and "licks up spilled milk.

"[61] Lewis Corner of Digital Spy considered it "easily one of the hottest of her career so far", adding that "the pair look absolutely flawless in the seductive visual.

"[58] Cady Lang of Time wrote that the "unabashedly 'pop' feel of the video brings to mind the Brit that we all knew and loved back during her heyday — that is to say that there's no shortage of body glitter, choreographed group dance routines, candy colored ensembles, and toned abs during this grown-up 'Slumber Party'.

[55] Less positively, Camp continued that the "Slumber Party" video did not explore the themes in Eyes Wide Shut, opting only to "[employ] sexuality—and homosexuality—purely for the benefit of the male gaze.

"[55] While naming it "a fun, outrageous, and expensive-looking clip", Anna Gaca of Spin opined that "it's miles better than the forced, brand-filled video for 'Make Me,' and the addition of Tinashe's vocals is enough to make you wonder why they ever released the song without her.