If you receive a federal student loan, you will be required to repay interest on it as well. The interest rate varies depending on the loan type and (for most types of federal student loans) the first disbursement date of the loan. Interest has a relatively high impact on how much money you will pay over the life of the loan. Interest rates on federal student loans are set by federal law, not the U.S. Department of Education.
Most loans disbursed (or paid out) before July 1, 2006* have variable interest rates that are adjusted each year on July 1. These rates are reported yearly in the Congressional T-Bill. The best historic break down of these changes that is fairly easy to read can be found here. If you'd like to switch your variable rate loan to a fixed interest rate, you may consolidate it, and you can read more about the implications of consolidation and interest rates here.
Federal loans disbursed after July 1, 2006 have fixed interest rates that do not change, but the specific fixed interest rate that applies to an individual loan depends on when the loan was first disbursed. Generally speaking, Undergraduate Direct Subsidized or Unsubsidized Federal Stafford Loans will have the lowest rates. Next will be Graduate or Professional Direct Unsubsidized Loans.** Direct PLUS Loans (Parents and Graduates) are known to have the highest interest rates of all federal student loans available.
Perkins Loans (regardless of the first disbursement date) have a fixed interest rate of 5%.
For more information about your interest rate, please contact your loan servicer directly.
*No new FFEL Program loans have been made since July 1, 2010. This means that variable interest rates are no longer available.
**As of July 1, 2012, graduate or professional students are no longer eligible to receive subsidized loans.