The couple sparked engagement rumours last Christmas when she posted pictures of herself wearing a ring.
She told Vogue that Turner had the ring made for her after consulting with her best friends and sister.
"It's so me. It's nice to know the person that you're going to spend the rest of your life with knows you very well."
They have not yet set a wedding date, with Lipa saying she must first finish her current world tour - which ends in Mexico in December - and Turner is busy filming.
He is due to play the lead in the Apple TV sci-fi series Neuromancer, adapted from William Gibson's 1984 novel.
"We're just enjoying this period," she said. "I've never been someone who's really thought about a wedding, or dreamt about what kind of bride I would be. All of a sudden I'm like, 'Oh, what would I wear?'"