Swift, 22, collaborated with the 21-year-old British singer-songwriter on her track 'Everything Has Changed' for her new album 'Red' and has invited him to support her for all 45 shows in her tour next year.
With the pair regularly messaging each other, Swift and Sheeran are getting "increasingly close", according to a source.
Swift recently posted a picture of the pair looking cosy together on Instagram.
The 'Lego House' hitmaker unveiled his new 'Red' tattoo on his forearm dedicated to Swift's new album. The tattoo is identical to the album's font.
Swift has previously described Ed as one of her "favourite people in the world" and said fans can expect more collaborations between them in the future.
"We had both reached out to each other's camps at the same time. I showed up at his hotel in Arizona and we just wrote songs all day. Then he came and hung out at my house in Los Angeles and we spent all night sitting on the kitchen floor laughing, writing songs and harmonising." she said.
