Joe Alwyn: Taylor and Joe Alwyn have been dating since 2016, and many fans believe that "State of Grace" is about him. The song talks about finding someone who makes you feel like you can finally relax and be yourself, and it seems like Taylor has found that with Joe.
Harry Styles: Taylor and Harry Styles dated briefly in 2012, and many fans believe that "State of Grace" is about him. The song talks about a relationship that was intense but ultimately didn't work out, and it seems like Taylor's relationship with Harry was exactly that.
John Mayer: Taylor and John Mayer dated briefly in 2009, and many fans believe that "State of Grace" is about him. The song talks about a relationship that was full of drama and heartache, and it seems like Taylor's relationship with John was exactly that.
Ultimately, only Taylor knows for sure who "State of Grace" is about. However, it is clear that the song is about a very important relationship in Taylor's life.