25 is the third studio album by English singer-songwriter Adele, released on 20 November 2015 by XL Recordings and Columbia Records. The album is titled as a reflection of her life and frame of mind at 25 years old and is termed a "make-up record". Its lyrical content features themes of Adele "yearning for her old self, her nostalgia", and "melancholia about the passage of time" according to an interview with the singer by Rolling Stone, as well as themes of motherhood and regret.

In contrast to Adele's previous works, the production of 25 incorporated the use of electronic elements and creative rhythmic patterns, with elements of 1980s R&B and organs. Four singles were released to promote the album, with "Hello" becoming an international number one song and the fastest selling digital single in the US, with over a million copies sold within a week of its release, "Send My Love (To Your New Lover)" charted within the top 10 and "When We Were Young" and "Water Under the Bridge" charted within the top 20 across Europe and North America.

25 received generally positive reviews from music critics, who commended its production and Adele's vocal performance. 25 became a massive commercial success, debuting at number one in 32 countries and breaking first-week sales records in multiple countries, including the UK and US. In the US, the album sold over 3.38 million copies in its first week of sales, marking the largest single-week sales for an album since Luminate Data began tracking point-of-sale music purchases in 1991. 25 was the world's best-selling album of the year for 2015, with 17.4 million copies sold within the year, and has gone on to sell over 23 million copies worldwide, making it the fourth-best selling album of the 21st century, the second-best selling album of the 2010s (behind 21), and one of the best-selling albums of all-time. Following 21, it was certified Diamond by the RIAA, making Adele the only artist of the 2010s to achieve this certification with two albums.

Credited for impacting the music industry by encouraging a renewed interest in buying physical releases rather than downloading or streaming and much like 21, for saving the dwindling sales of the global music industry, 25 won the 2016 Brit Award for British Album of the Year, and the 2017 Grammy Award for Album of the Year. To promote the album, Adele embarked on her third worldwide concert tour, Adele Live 2016. It started on 29 February 2016 and ended on 30 June 2017. The concert broke numerous attendance records across the globe and grossed $167.7 million.