Nicole Richie loves being called "Mrs. Madden" since she got married.

The fashion designer tied the knot with Good Charlotte rocker Joel Madden two months ago after dating him for four years, and says one of the best things about getting wed has been taking her husband's surname.

She told People: "I just went to Ireland, and it was really the first time I was called Mrs. Madden. The people were asking me if my last name is Madden, and I was like, 'Yeah, my last name is Madden now.' And they were like, 'You're one of us!' And I was like, ‘Oh, hell yeah I am!'

"It's awesome to be known as Mrs. Madden. It's music to my ears."

The 29-year-old star – who has two children, Harlow, two, and 18-month-old Sparrow, with Joel – also joked that her name change in everyday life has made it easier for her to go on expensive shopping sprees.

She said: "I can take his credit card and buy anything with it without anyone questioning me about it. That's definitely one thing I'm loving."

The couple married on December 11 last year at Nicole's father Lionel Richie's Beverly Hill estate.