#1 to Infinity is the third compilation album by American singer Mariah Carey. It was released on May 18th, 2015 through Sony Music Entertainment. The album is a collection of her 18 number-one songs in the United States, and also includes a brand new song titled "Infinity" which was released as a single from the album on April 27, 2015.#1 to Infinity is being released to coincide with the launch of her Las Vegas residency show at The Colosseum at Caesars Palace,
which is set to begin on May 6, 2015. The singer launched a social media campaign with the hashtag #RevealMariah early on April 12 which encouraged fans view her website, where they were then prompted to share news of the reveal in order to expedite the lift of the album's official cover art. The album is her first for Sony Music's Epic Records, with whom she signed in March 2015.
The album features Carey's 18 number-one songs in the United States, with a brand new song titled "Infinity". The track listing is adjusted for the international markets; "Someday", "I Don't Wanna Cry" and "Thank God I Found You" (featuring Joe and 98 Degrees) are replaced with "Without You" (number one in most European countries and New Zealand), "Endless Love" (with Luther Vandross, number one in New Zealand) and "Against All Odds" (featuring Westlife, number one in the UK and Ireland).
The only new recording to be included on the compilation, "Infinity", premiered on April 27, 2015, to coincide with Carey's Las Vegas launch party. The accompanying music video was directed by Brett Ratner.
On January 15, 2015, Carey appeared on The Ellen DeGeneres Show to announce that she signed a contract to take up residency at The Colosseum at the Caesars Palace hotel in Las Vegas in May and July 2015; it is called Mariah Carey #1's. During the interview, Carey confirmed "I'm going to do my first ever residency in Vegas at Caesars." "This is a special event for me. And again, I have to hope that the fans will enjoy this cause I'm gonna be performing, which was kind of inspired by my album #1's, and this is now the updated version with eighteen of them. Hopefully other people will enjoy this. I've never done this before." The confirmation of Carey's residency came after Canadian singer Celine Dion announced that she has postponed dates of her residency at Caesars Palace to care for her husband, René Angélil, who is suffering from cancer. In March 2015, Dion confirmed that she will return to Caesars Palace in August to continue her residency following the departure of Carey.