Bubbly" was written by Colbie Caillat and Jason Reeves. It is an alternative pop song, folk song, and acoustic song. "Bubbly" is written in the key of A and primarily features a gentle guitar instrumentation which uses a capo of 7th fret.[1] The guitar uses open D tuning (low to high): D-A-D-F♯-A-D.[2]
Caillat commented on the lyrical composition of the song in an interview with Wilson Country News on 20 February 2008, following her live performance on The View, "I didn't write "Bubbly" for any [special] guy. I wrote it about the feelings you get when you have a crush on somebody, and when they give you butterflies in your stomach and they just make you smile