But what peeps don't know is how they met.
Since Taylor has been laying low for the past year while working on her upcoming album, where on earth would she meet such a handsome gentleman?
It turns out that it was a setup.
Tay's bestie Emma Stone is currently working with the baben actor on The Favourite, a movie about the reign of Queen Anne.
After meeting Joe, Emma thought that he would be a PERF match for her pal, Tay and set the pair up on a date.
Following this, Tay has been flying to London and back for "several months," wearing disguises like hats and scarves to keep the relationship on the down low.
Iiiiiiinteresting. So THAT'S why she no one has known about Taylor's new relationship until now.
Sneaky Tay, sneaky.