The singers took to the stage to perform Goulding's 2013 hit 'Burn' at the O2 Arena for the final UK date of Swift's Red world tour.
It marks the second time the pair have duetted during one of Swift's shows, after they performed Goulding's 'Anything Could Happen' in the US last year.
Swift sang with Emeli Sandé in London on Monday night (February 10), while also duetting with The Script's Danny O'Donoghue, Ed Sheeran and Sam Smith during her UK shows.
It also marked the last date of Swift's Red world tour, which started in North America back in March 2013.
The jaunt saw the star travel across North America, Europe and Australia, breaking a record at the Allianz Stadium in Sydney by becoming the first female solo artist to sell out the venue since it opened in 1988.