There are no copies of your Certificate of Naturalization. If your certificate has been lost or stolen, you must apply for a new document. This is done by filling out an N-565, Application for Replacement Naturalization/Citizenship Document. This form can be found on the U.S. Citizenship and Immigration Services (USCIS) website. USCIS does not accept the N-565 in their office unless it is an extreme emergency. Normally, you must mail the form, along with a letter explaining your request and requesting for a confirmation receipt. USCIS recommends sending mail to them through a third-party delivery service (FedEx or UPS) or by registered U.S. Mail. For additional information, contact the USCIS at (800) 375-5283.