The 'Lost' co-stars - who abandoned plans to marry in 2007 after two years of dating - rekindled their romance last year and are now said to be making plans to tie the knot after the British star sought advice from his family.
A source told National Enquirer magazine: "Dominic and Evangeline have decided that now is the time to make it official.
"They've been through break-ups and make-ups and feel that their love has stood the test of time. But it was very important for Dominic to let his parents know what their intentions were.
The couple, who met on the set of the hit US show, found their time apart showed them just how much they loved and missed one another.
The source added: "They never stopped loving each other after their split. They decided to take a break, but it was really hard on them both."