The Prince of Wales also did the honors for a family friend back in 2016.
After her father, Thomas Markle, backed out of doing the honors earlier this week due to health complications, Kensington Palace revealed on Friday that Meghan's soon to be father-in-law, Prince Charles, will be stepping in.
"Ms. Meghan Markle has asked His Royal Highness The Prince of Wales to accompany her down the aisle of the Quire of St George's Chapel on her Wedding Day," the palace said in a statement. "The Prince of Wales is pleased to be able to welcome Ms. Markle to The Royal Family in this way."
According to CNN, Meghan will begin the bridal processional unescorted, followed by her bridesmaids and page boys, and Prince Charles will join her when she reaches the Quire -- the area where the main royal guests will be seated. He will then walk her to the foot of the altar, where he will not "give her away" but instead stand back as Meghan approaches Harry herself, breaking tradition.
While fans were surprised to hear Meghan chose Prince Charles (many expected it to be her mother, Doria Ragland, or future brother-in-law, Prince William), it won't be the first time the Prince of Wales has walked a bride down the aisle.
In 2016, Charles did the honors for family friend Alexandra Knatchbull -- who is reportedly Princess Diana's goddaughter -- at her wedding to Thomas Hooper.
ET spoke with royal expert Katie Nicholl on Friday, who gave us some insight how the decision for Prince Charles to walk Meghan down the aisle was made.
"Well, it wasn't just Meghan's idea," she said. "From the canopies to the champagne to who will walk Meghan down the aisle was made by both [she and Harry] together. I think, really up until last night, they were sort of talking about how this was best going to work and they agreed that it should be Charles. But it was in fact Meghan who asked the Prince of Wales if he would do her the honor of walking her down the aisle."
In a statement released on Thursday, Meghan officially announced that her father would not be attending her nuptials. "Sadly, my father will not be attending our wedding. I have always cared for my father and hope he can be given the space he needs to focus on his health," she said. "I would like to thank everyone who has offered generous messages of support. Please know how much Harry and I look forward to sharing our special day with you on Saturday."
Hear more in the video below, and keep up with all of ET's coverage of the royal wedding as we count down to Meghan and Harry's big day!