But the design is so classic that it's super easy to find without resorting to dropping major cash for the Tom Ford original!
We found two equally affordable options that are super similar to Kate's dress.
Check 'em out ...AFTER THE JUMP!!!
The designer and her mini-me Harper arrived at LAX airport from London on Thursday looking totally unaffected by the hours-long plane ride and time change.
Posh embraced a looser look in striped Chloe pants, a sleeveless, belted coat from her own A/W 2013 collection and Casadei pumps.
Meanwhile, Harper was super chic in a white eyelet button-down, jeans, and suede booties!
It's like these two are having a mother-daughter fashion show every single day!
[Image via Ramey Pix.]