European BS - American PhD (Graduate Admission) I posted something similar a while back and it was closed, but I believe this post will be more suited for discussion. 

I'm heading to Europe from the U.S. to complete my BS in physics. I intend on returning to the U.S. to complete a PhD (ie. no masters degree in-between). I'm aware that the European system has a three year BS program, as compared to the four years that are done in the U.S. 

The central question is: Does having a three year BS affect admission into a competitive American graduate program? 

From where I sit, I can't help but feel PhD programs will raise an eyebrow at applying with only two years of experience. All of the graduate application deadlines available online (Princeton, Cornell, Columbia) have a deadline of the 15th of December, which correlates to a little over two years of undergraduate education. 

I've been lucky enough to have a huge head-start on the material (few formal credits, however), which means I could start research within my first year of study.
I don't think there will be a huge problem in taking a European bachelor's degree to a US institution, so long as you do a little explanatory work in getting ready to apply. The reason for this is that in those first two years, you will often have more major-specific work than most US students will have completed in three years!

So, I would recommend contacting the graduate admissions of programs you're interested in applying to, and explaining your situation to them. Take a look at the undergraduate programs they offer—and in particular, the list of required courses, and show that you have a similar amount of preparation (or more!). Then ask if there's anything else that you need to do.