The One Direction heartthrob is completely smitten with the Love Story singer and friends believe the pair are even considering marriage, even though they only recently started dating.
A source told Us Weekly: "This [relationship] has gone from zero to 60 in seconds.
"Harry is totally in love. I can see them getting married in a week, just going for it."
Things are so serious between the couple that Taylor, 23, recently visited 18-year-old Harry's mother Anne in Cheshire, North West England, and is reportedly planning to buy a country retreat there.
A source previously said: "Harry and Taylor are crazy about each other. They just got back to LA together, after sharing a week-long vacation in England.
"While they were in the UK, they had a chance to drive up to Harry's mom's place in Cheshire and Taylor fell in love with the gorgeous countryside.
"They spent a day in Holmes Chapel, with Harry's mom Anne and his sister Gemma, before driving up to the Lake District.
"Taylor would love a really old, thick-walled cottage with a fire place.
"Harry's mother and sister have vowed to help her find the perfect place!"
- BANG! Showbiz