The Mamma Mia! actress split from the Pearl Harbor hunk in April (12) following a brief romance and now the blonde beauty is dating Harrington, who plays Detective Joseph Quinn in the hit U.S. show.
The pair was spotted hand-in-hand during a day out in New York on Monday (27Aug12).
Harrington is Seyfried’s latest actor beau – she has also dated her Mamma Mia! co-star Dominic Cooper and Ryan Phillippe.