[26] During the sessions in Los Angeles she also wrote "When We Were Young" alongside Tobias Jesso Jr., the track was written at a rented house where Adele used Philip Glass' piano.

[9] Shortly after this, Adele began work on the track "Send My Love (To Your New Lover)", reworking a skeleton of a song she had written when she was thirteen years old after being inspired by the release of Frank by Amy Winehouse.

Consisting of eleven tracks, Adele aimed to depart from the "young-fogey" sound of her second album 21 and added synths and drum pads to modernize 25's musical style.

[37][38] Described as a collection of "panoramic ballads and prettily executed detours", Leah Greenblatt of Entertainment Weekly noted the album's "stately production" characterizing it as being built over minor-key melancholy, stylistic flourishes and simplicity.

[43] Bruce Handy of Vanity Fair stated that Adele's throat surgery had not impacted her voice, continuing to say her voice still contained character and power: "brassy yet husky, smoky yet clarion, she still sounds like the result of a genetic experiment fusing Amy Winehouse's vocal chords with Céline Dion's lungs, or even Tom Jones'.

"[45] Lyrically, the album touches upon various themes including the singers fear of getting older, her childhood, regrets, longing for her family, nostalgia and her role as a mother.

"[46] The album is focused at a broad popular music appeal, where her former releases, were made with a concoction of "gospel, R&B, jazz, [and] folk" styles, elements, and audiences in mind.

[49][50] During the chorus Adele is heard singing the lines over layers of backing vocals, piano and drums which were described by the Telegraph as leaning "towards a very luscious wall of sound".

[53] The follow-up, "Send My Love (To Your New Lover)", has been compared to the work of singer Taylor Swift[54][55] due to its "upbeat, poppy" sound.

[57] The drum-filled folk song "I Miss You"[58] has been described as "explicitly seductive" due to the lyrics: "Bring the floor up to my knees/Let me fall into your gravity/And kiss me back to life to see/Your body standing over me.

[64] "Million Years Ago", an acoustic tune accompanied only by guitar, finds the singer pining "for the normality of her not-so-distant childhood.

[74] On 27 October, BBC One announced plans for a one-hour television special presented by Graham Norton in which he would talk to Adele about her new album.

[87] Adele also conducted interviews with and appeared on the covers of Time,[88] Vanity Fair,[89] Vogue,[90] i-D,[91] The Observer,[92][93] and Rolling Stone.

[97] The song sold 1,112,000 digital downloads and 61.2 million streams in its first week, resulting in "Hello" debuting at number one on the Billboard Hot 100 (becoming Adele's fourth number-one single in the United States) on the issue dated 14 November 2015.

The first leg started in Belfast on 29 February 2016 in the SSE Arena before moving throughout mainland Europe and concluding in Antwerp at Sportpaleis on 15 June 2016.

[102] The second leg began on 5 July at the Xcel Energy Center in Saint Paul, Minnesota and continues throughout the United States and Canada with multiple dates at each venue.

[1] Reviewing for AllMusic, Stephen Thomas Erlewine comments, "Fittingly, 25 also plays better over the long haul, its march of slow songs steadily revealing subtle emotional or musical distinctions", where "all 11 songs are ... a piece ... [of] shaded melancholy gaining most of their power through performance", and arguing that the "cohesive sound only accentuates how Adele has definitively claimed this arena of dignified heartbreak as her own".

[106] Neil McCormick from The Daily Telegraph stated that the album covered the same "musical and emotional terrain" as 21 and continued to call it an "equal of its predecessor.

"[107] Jon Dolan of Rolling Stone commented that the album's "nostalgic mood is the perfect fit for an artist who reaches back decades for her influences, even as her all-or-nothing urgency feels utterly modern" and also praising her "incredible phrasing – the way she can infuse any line with nuance and power", which he argued served as "more proof that she's among the greatest interpreters of romantic lyrics".

[64] Leah Greenblatt of Entertainment Weekly called it "a record that feels both new and familiar—a beautiful if safe collection of panoramic ballads and prettily executed detours".

[39] Billboard praised Adele's vocal performance writing that it's "swathed in echo, sounding like she's wailing beneath the vaults of the planet's most cavernous cathedral, they hit hard.

[110] In a less enthusiastic review for The Independent, Andy Gill said the songs "River Lea" and "Send My Love (To Your New Lover)" were "isolated moments of musical intrigue scattered here and there through the album", which he said gradually became "swamped by the kind of dreary piano ballads that are Adele's fall-back position".

[109] Leonie Cooper from NME felt Adele and her team of songwriters/producers did not take any risks musically, instead "following a formula that has so far resulted in 30 million album sales".

[40] Jude Rogers found the 25 bogged down by the emotionally weighty themes of Adele's previous records, comparing the singer to "a friend who you've helped countless times but who won't listen, who actually enjoys being in a mess, whose sparkle gets dampened – gets drowned – as a consequence".

[150][151] In December 2016, it became only the third album to be the UK's biggest-seller two years in a row, after Simon & Garfunkel's Bridge over Troubled Water (1970 and 1971) and Simply Red's Stars (1991 and 1992).

[153] In Europe, 25 also opened atop of the German charts after selling 263,000 units, the largest weekly sale for a record since Herbert Grönemeyer's 2007 release 12.

25 was also the second biggest-selling album of a calendar year by a female artist in Nielsen history, only trailing behind Britney Spears' Oops!...

[195] In October 2015, numerous journalists speculated that other musicians had pushed back their album releases to avoid chart competition with Adele; artists such as Justin Bieber, Rihanna, Sam Smith, and One Direction all did this so that their sales would not be affected.

Adam Sherwin of The Independent stated that "25 sent casual purchasers back to the remaining physical stores and may even have introduced a new generation to the delights of ownership.

Target Chief Executive Brian Cornell stated that 25 was "the biggest release we've ever had – this is going to break all the records for us" and that "the combination of Adele dropping when it did, the weekend before Thanksgiving, really helped bring in people".