Unstoppable is the sixth studio album by American country music group Rascal Flatts and their final album to be released with Lyric Street Records. It was released on April 7, 2009 and produced four singles on the US BillboardHot Country Songs chart. The album debuted at number one on the Billboard 200 in the U.S. with 351,000 copies sold, making it the band's fourth consecutive number-one debut on the chart. It topped the 1 million mark on October 31, 2009. As of June 2010, the album had sold over 1,230,638 copies in the United States.
The first single, "Here Comes Goodbye", was released on January 20, 2009. The song was co-written by American Idol season 6 finalist Chris Sligh. Rascal Flatts will tour in support of the album on the Rascal Flatts American Living Unstoppable Tour, presented by department store chain JCPenney. Editions sold at JCPenney include the bonus track "American Living". "Summer Nights" was released as the second single from the album on May 19, 2009. It reached number 2 on the Billboard Hot Country Songs chart. "Why" was released as the third single from the album on September 29, 2009. It became their lowest-peaking career single to date, peaking at number 18 on the aforementioned chart. "'Unstoppable" was released as the album's fourth single on January 4, 2010, and was a Top 10 hit on the Billboard country chart.
The album overall gained mixed reviews. Matt Bjorke of Roughstock gave the album a favorable review. Similar to his later review of the single "Summer Nights,", Bjorke commented that the album would appeal to fans of Rascal Flatts, but would unlikely bring new fans to the group. He specifically cited "Why" as the best track of the album, writing, "This is the kind of song that got me to personally like Rascal Flatts and it's certainly the best track on 'Unstoppable'" and "There's gotta be 'Song of the Year' accolades somewhere down the line for this song as it's that powerful."