Beverley Mitchell and Michael Cameron
Djamilla Rosa Cochran/WireImage
The pair, who are both 25 and have been dating for five years, got engaged on New Year's Eve in Colorado.
"They really are a good fit for each other. Her friends and family are thrilled," a source close to the couple tells PEOPLE.
Mitchell's engagement ring is a 3.5-carat yellow diamond by designer Louis Glick. This will be the first marriage for both the actress and Cameron, who plan to wed next year.
Mitchell, who grew up in Arcadia, Calif., plays middle-child Lucy Camden on the WB drama, which debuted in 1996. She also has appeared on Quantum Leap, Melrose Place and in last year's horror flick, Saw II.
