Her husband, Prince Frederik also beamed alongside his wife for the second New Year’s reception hosted by Queen Margrethe of Denmark at Christiansborg castle in Copenhagen.
The Prince – who has most recently opted for a clean-shaven look – appeared dapper in military regalia.
It’s been a busy few days for the royal couple – with the pair stepping out for a variety of occasions.
Mary stunned in a tiara at a New Year’s banquet before appearing in a recycled blue gown for another reception.
Days later, Prince Frederik attended a Sport of the Year show in Herning – where he announced Danish tennis player Caroline Wozniacki as an award-winner.
Wozniacki was not present at the awards ceremony as she was in Australia preparing for this year's Australia Open, which starts in a week's time.