Cox, 50, and her soon-to-be husband were given a friendly welcome to the city when they touched down at City of Derry Airport on July 23 after a romantic getaway to London, reported Hello! magazine.
Dressed in a burgundy top and jeans, the actress happily posed for pictures with airport staff.
Earlier this week, the newly-engaged couple were seen arriving at Heathrow along with Cox's 10-year-old daughter, Coco, from her relationship with ex-husband David Arquette.
The 'Cougar Town' actress announced her engagement to the musician on Twitter in June after six months of dating.