Download the Department of State form DS-5504. A link to this form can be found in the Resources section of this article. Print the form and fill out the requested information as completely as possible. Section 18 of the form is where you can enter the name, address, and telephone number of your new emergency contact. Even if you are only changing the information of your emergency contact, you must complete the entire form.
Mail the completed form, your most recent U.S. passport, and two recent color passport photographs to: National Passport Processing Center, P.O. Box 90107, Philadelphia, PA 19190-0107.
Keep in mind that there is no fee for this service, and you will typically receive your new passport in four to six weeks. There is also an expedited service available. To utilize the expedited service send the same items listed in Step 2 to the National Passport Processing Center, P.O. Box 90907, Philadelphia, PA 19190-0907. There is a $60 fee for expedited service and the turn time is typically two to three weeks.