Tegan wrote the majority of the song, but Sara and Greg Kurstin collaborated with her on the chorus. She recalled to Under The Radar
: "By the time we'd gotten to the studio I'd rewritten the song, like, six times. The bridge, as it is right now, used to be the chorus. As the song got bigger and bigger, and more and more poppy, we all felt like the chorus seemed too mellow. I'd sort of been influenced by Erasure and Ace of Base when I wrote 'Closer,' and that was sort of what I was trying to emulate: my favorite, mid-'90s dance tracks. I felt 'Closer' was more mellow than it needed to be, so we wound up co-writing."