This is the pair's first engagement together, without their husbands Prince Harry and Prince William.
The ladies final will be the first royal engagement that Meghan and Kate have carried out together and before sitting down to watch the tennis they will be meeting previous Wimbledon champions as well as some of the ball boys and girls.
Kate's dress was a vast difference from the Duchess of Sussex's outfit, after she chose to wear a pair of wide-legged, white pants and a striped shirt.
Time to move on up to the royal box!
On Saturday, Kate Middleton and Meghan Markle will be making their first solo appearance together without their husbands, Prince William and Prince Harry, for the Ladies' Single Final at the Wimbledon Championships, Kensington Palace announced on Thursday.
"We always have supported each other, just been there for each other through a lot", said Serena.
"Every year, for a couple years, she comes out to Wimbledon, has supported me". Knowing that no matter what happens, I have fantastic support and unconditional love. "But our friendship is still exactly the same", Serena said of Meghan. "I look forward to it", she said.
Surprise! Kate Middleton makes appearance with royal family at RAF celebration
In June, she was spotted alongside the rest of the Royal family at the Trooping of the Colour, the Queen's birthday parade. On Monday, Prince Louis was christened at the Chapel Royal in St James's Palace surrounded by his family.
Williams gave birth 10 months ago and is the first mother to reach the last round of the tournament since Australian Evonne Goolagong in 1980.
Saturday sees the women's Wimbledon final take place, and after a strong tournament so far, our tennis columnist, Dan Weston, previews the match.
Anderson and Isner's match was the second-longest in Wimbledon, behind only Isner's record 11-hour, five-minute first-round triumph over Frenchman Nicolas Mahut in 2010.
The interrupted men's semi-final between Novak Djokovic and Rafa Nadal is scheduled to continue prior to this final, with our even-money recommendation from yesterday, Djokovic, 2-1 to the good.
Due to the epic men's semi-final between eventual victor Kevin Anderson and John Isner that lasted six hours and 36 minutes, Serena Williams and Angelique Kerber's clash for the ages might not start on time.