It is always best to determine if you have federal or private student loans, and who services them before you start the refinance or consolidation process.
To find your federal student loans: Log into your My Federal Student Aid account with the U.S. Department of Education. Or call the Federal Student Aid Information Center at 1-800-4-FED-AID (1-800-433-3243).
To find your private student loans: Request your free annual credit report (yes, it's really free, and it's legit) at AnnualCreditReport.com. The balances and lender information for your private student loans should be listed in your report. You will need this information to refinance.