Your loan servicer is the organization that handles billing you for your loan. Direct Loan borrowers are assigned a loan servicer after the first disbursement of their loan. Your loan servicer will contact you directly after you receive your first disbursement.
If you're not sure who your loan servicer is, you can look it up on www.nslds.ed.gov or call the Federal Student Aid Information Center at 800-4-FED-AID (800-433-3243; TTY 800-730-8913). To see a list of Federal Student Aid servicers for the Direct Loan Program and for FFEL Program Loans purchased by the U.S. Department of Education, go to the Loan Servicer page.