Go to the travel.state.gov website.
Read the "Privacy" notice and click the box indicating that you have read the notice. The website will not let you continue without this step.
Enter your last name, date of birth and the last four digits of your social security number. Click Submit. The next screen will list your passport's status.
Call the National Passport Information Center at 1-877-487-2778 or email them if it looks like the passport may not arrive in time for your travel needs. You may be able to expedite your passport for a fee.