Marissa,

As a holder of a US passport, you do not need your CH Permit B to enter. owever, you will need it (to avoid problems) if you leave CH after having stayed in CH longer than 3 months.

Once back, you can go to OCP and request a new one.

Good luck, and hope no one got hurt.

Providing you will return to Switzerland with the 3 documents you are listing, there won't be much delay at border post. US citizens are most welcome when they visit, even as tourists ;)

For OCP proceedings thereafter, you need to add a copy of your rental contract and an attestation of employment (or a copy of your current work contract) when applying for a new permit. Well planned since you scanned your B permit showing reference number thus makes replacement a lot easier. You might also need to collect a No-claim Attestation(attestation non poursuite) as a bonus.  Just make sure the OCP files the previous original was stolen in order to protect you should the thief tries a fraudulent use on swiss grounds...

Hi,

You will have no issue re-entering Switzerland as your US passport is enough.
But yes, you will need to go get another one when you come back in Switzerland.

Cheers,
M. 

Why would she need to re-apply for a residence permit?!? She just needs a duplicata issued whicj will likely not be free like everything else in Switzerland, that's all.

Marissa wrote OCP told her how to get a new residence permit... True ! Things are simpler for collecting a duplicate parmit. Additional docs would be necessary however if there was a change in her residence and/or professional status since she received previous B document.

Thanks for your useful responses.

Actually, I am in Geneva on a Permis B (etudiant(e)), so I shouldn't need any sort of proof of employment or my rental contract. This would not be a renewal of my permit (since it expires in September 2013 and renewed it back in September 2012), but rather simply a re-print. And actually, the OCP already told me what I need to get a reprinted permit: the police report, my passport, and 67CHF.

My question was purely related to reentry, because I know sometimes they are picky about making sure you have your Permis on your person, even if you have a passport that shouldn't normally present entry problems.

Thank you everyone! I feel much better now :) and no one was hurt, just a bit of bad luck and cunning con artists who purposely target foreigners.