Check the following Link for nationals of non-signatory states
http://www.ahv.ch/Commun/10.03-D-F-I-A.pdf See point 18 on page 52. "Nationals of non-signatory states who live abroad may
apply for reimbursement of their OASI contributions without interest, if they
have definitively left Switzerland.
They must have paid contributions for at least 1 full year to be entitled to
this reimbursement."
It looks like AHV (Old Age & Survivors Insurance or OASI) can be paid out when you leave if you are a resident of a non-signatory state. Page 45 of the document lists the signatory states.
The form for actually claiming the OASI refund when you leave is as follows:
http://www.ahv.ch/Commun/602101-e.pdf
The deductions for AHV are about 5% so can add up if you are here for a while.