A source tells ET that Markle "arrived in London last night. She landed at Heathrow aiport around 9 p.m. and went straight to Kensington Palace."
ET previously reported that Markle had requested a week off from filming her USA legal drama, Suits, to join her boyfriend, Prince Harry, for Middleton's wedding. According to multiple reports, Markle will be attending the ceremony with Harry, in addition to the reception.
Middleton will be saying "I do" to her fiance, James Matthews, at St. Mark's Church in Englefield, England. Her sister, Kate Middleton's, children, 3-year-old Prince George and 2-year-old Princess Charlotte, will both have roles in the ceremony as a page boy and bridesmaid, respectively. A lavish reception will follow at the Middleton family home in Bucklebury, England.