What is the naturalization certificate number?
On the upper right hand corner of a U.S. Naturalization Certificate is a number used to keep track of certificates. This number is connected to the recipient in their citizenship file for future reference. If a U.S. citizen loses their naturalization certificate, they must supply the certificate number for a replacement document.References:Naturalization CertificatesU.S. Citizenship and Immigration Services: Application for Replacement Naturalization/Citizenship DocumentResources:U.S.