Songfacts®:

• Pentatonix teamed up with actress/singer-songwriter Taylor Parks, who also penned Fifth Harmony's "Bo$$," to write this song that leaves the narrator with the upper hand in a broken relationship: "You ain't gonna win, 'cause I'm the ref."
  
  Scott Hoying, the group's baritone vocalist, explained: "It's so funny 'cos the lyrics…we didn't start out with the concept that it was going to be about like a referee and that type of thing but it just kind of turned into that. And I remember Taylor Parks going: 'Keep on going 'cos I'm no ref.' We all just like screamed. We just jumped up so excited. And we were like: "The name of the song is 'Ref' and we were like so pumped about it."
• The a cappella group used a real whistle to accompany the "I'm the ref," lyric. Hoying said: "The biggest struggle with the song was deciding if we wanted to emulate a whistle sound or use a real whistle, because we feel like we were losing integrity using a real whistle. But we decided to push ourselves and move forward and be progressive and so we used a real whistle.