It debuted at #31 on Billboard's Hot Adult Top 40 Tracks chart. and has since become Train's second-consecutive #1 hit from the album, as well as their fourth #1 overall. This ties the band with Matchbox 20 and Daughtry for second-most chart-topping singles in format history, and trailing only Nickelback in total Adult Top 40 #1 placements. It is also the 100th single to go #1 in the format's history.

In addition, it has reached #34 on the Billboard Hot 100.

A music video was filmed for the song, which debuted on VH1.com on May 11, 2010.

In a 2010 interview with The Post-Crescent, Pat Monahan confirmed "If It's Love" was written the same day as their hit "Hey, Soul Sister" and was intended as a thank-you song to long-time fans of the band:

This song was actually written on the same day as "Hey, Soul Sister" in New York City. I wrote this song first in the day, and I was thinking about all these people who have been supportive of the band Train for so many years. I had also made a solo record, and (fans) were really supportive to me and I was just like, "I wanna write a love song finally after all these years, but I wanna write it to our fans and just say thank you."

Much like "Hey, Soul Sister", the track features a handful of pop cultural references including Winger (an American hard rock band that enjoyed popularity in the late 80s and early 90s), and "The Rain in Spain" (a song featured in the musical My Fair Lady).

In addition, the lyrics "There's no happy endings, No Henry Lee" refer to the inscription and the main character in Jamie Ford's 2009 novel Hotel on the Corner of Bitter and Sweet.

In a 2010 interview, Monahan explained the lyric "I wanna buy you everything except cologne, 'cause it's poison."

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Wikipedia