A customer asked me about this recently, and for some reason I had forgotten how to do this. So I thought I’d write it down here in hopes that it might help someone else.
The problem: You have an Illustrator file that contains multiple Artboards, and you want a quick way to save each Artboard as a separate .AI file.
The solution: Simple. Just choose File > Save As, and in the Illustrator Options dialog box, select Save each artboard to a separate file.
If your Illustrator file is named “MyIllustratorFile”, when you save the artboards, they will be named MyIllustratorFile-01.ai, MyIllustratorFile-02.ai, etc.
I think I had trouble finding this because it only shows up when you do a Save As, or the first time you Save a new file. I guess I was expecting some sort of an export artboards command or something instead. Anyway…its simple, and pretty obvious when you look in the right place!
This ability goes back at least as far as Illustrator CS6, maybe even further. Also, when you choose File > Export to output to png, swf, jpg, psd, tif, or svg, you have the opportunity to output each artboard to a separate file.