From designer wedding dresses to chic high street buys, they've got royally good style (see what we did there?).
However, while Meghan isn't afraid of a daring hemline and Kate loves a zesty yellow dress, there's one colour the duo steer clear of.
Harpers Bazaar Australia pointed out that Kate and Meghan have never been spotted out and about in orange.
Meghan Markle stunned in Givenchy at the Fashion Awards... but broke royal protocol in this super subtle way
If you're an avid royal watcher, you'll probably have noticed, too.
While you may be quick to assume that it's down to royal rules, The Express believes it's for a much more simple reason.
According to the newspaper, it's all because tangerine doesn't photograph well - and when you're two of the world's most documented women, what you look like on camera is paramount.
While the royal sister-in-laws have avoided plumping for orange, it's actually set to become the hottest hue of the season.
A slightly more burnt, muddier shade of orange, we're calling it now that everyone will be wearing it next season.
Unashamedly autumnal... bright-but-not... fun-but-chic... it's a wonder why we haven't all been wearing this mature take on the hue already.
Perhaps Kate and Meghan will catch on? Here's our edit of some celeb inspo to get you started.