The Beatles legend Paul McCartney, 68, began dating American heiress Nancy Shevell, 51, in 2007, a year after ending his marriage to former model-turned-activist Heather Mills.
They have kept their relationship relatively low-key, although they stepped out together on Monday, May 2, to attend the annual MET Gala at New York's Metropolitan Museum of Art.
And now a report on People.com suggests the couple is ready to exchange vows.
A source tells the publication, "Nancy and Paul are getting married... Very exciting. They have the right chemistry. They're both cool, chilled out and optimistic."
A publicist for Sir Paul McCartney had yet to respond to a request for comment as WENN went to press.
If the reports are true, it will be McCartney's third trip to the altar. He lost his beloved first wife, Linda, to breast cancer in 1998 and was married to Mills for four years before their bitter split in 2006, which saw the star hand over $38.9 million (GBP24.3 million) to settle the divorce.