Certificate of Naturalization Number

Updated on April 4, 2024

At a Glance

  • Certificate of Naturalization Number (C-File Number): The certificate of naturalization number, also known as the C-file number, is issued to naturalized U.S. citizens. It is an 8-digit alphanumeric number printed in red on the certificate.
  • Identification and Distinction: The number distinguishes the individual as a citizen and is found on the certificate itself or court records.
  • Replacement and Correction Process: If the certificate is lost or needs correction, Form N-565 can be used to apply for a replacement, with supporting documentation.
  • Application Considerations: The application process can take up to a year, and it’s recommended to prepare thoroughly and seek assistance if needed.

The certificate of naturalization number can be quite an important number for many. The C-file number signifies the end of a long, arduous journey in acquiring U.S. citizenship. It is a guarantee of U.S. citizenship.

Individuals are generally asked for their C-file number when filling out forms for the United States Citizenship and Immigration Services (USCIS). Individuals are often asked for their file number, date, and place of issue. In this article, we will answer all the questions related to the naturalization certificate, the USCIS, and where you can locate all the information.

What Is a Certificate of Naturalization Number?

A certificate of naturalization number, also known as the C-file number, is a critical certificate issued to a naturalized citizen of the United States of America. Naturalized citizens obtain U.S. citizenship after applying for permanent legal residency and taking (and passing) the appropriate tests. Once the individual is sworn into the country, they are given a certificate of naturalization. The C-file number is an 8-digit alphanumeric number printed in red on the top right-hand corner of the certificate.

The certificate number must not be confused with other form numbers given in the entire USCIS application process. This includes the USCIS registration number, the petition number, the application number, or the CIS registration number. The certificate of naturalization number is an entirely separate numeric identity that indicates the individual’s citizenship and rights in the United States of America.

Who Has a C-File Number?

A C-file number can only be given to those who have applied and successfully gotten their U.S. naturalization. The C-file number is located on the certificate and establishes the individual as a naturalized U.S. citizen. The naturalization certificate also includes the date and place of when and where the applicant took the oath.

Where to Find Your Certificate of Naturalization Number

The certificate of naturalization number can be found on several documents. Here are some common examples of where you can find your certificate of naturalization number:

1. Your certificate number is always printed in red on an original U.S. certificate of naturalization document or any certificate of citizenship that has been issued after September 27, 1906.

2. Certificate numbers can also be found on certain court records like indexes in the court naturalization documents. Court indexes refer to various court petitions and declaration documents filed with the immigration court. As noted earlier, the certificate number and the petition file number are two separate individual documents. Examples of index cards produced in federal courts can be found in the National Archives.

3. Many forms filed after 1906 often contain a blank space for the naturalization certificate number. The individual can note their final certificate number in this blank space. As with index cards, examples for such petitions can be found in the court records at the National Archives.

How to Replace Your Certificate of Naturalization

If your certificate of naturalization is lost, misplaced, stolen, damaged, has an error on it, or if you’ve had your name and/or gender legally changed, you can replace it. It is handy to have the C-file number on hand while applying for the replacement. However, it is not mandatory. The overall application process is simple. However, be sure to enter your information carefully and correctly.

Here’s how to apply for a replacement naturalization certificate:

The primary way to apply for a certificate of naturalization is via Form N-565, Application for Replacement Naturalization/Citizenship Document. This application has to be submitted to the United States Citizenship and Immigration Services.

Form N-565 is mandated for reissuing citizenship documents when the individual is already a registered citizen of the United States. This form should not be filed if the individual falls into the following categories:

1. If the individual is a permanent resident applying for U.S. citizenship, they should file Form N-400, Application for Naturalization.

2. If the individual is a U.S. citizen by birth requiring an original copy of their certificate of citizenship, they should file Form N-600, Application for Certificate of Citizenship.

Here are some reasons why people might apply for a replacement of their certificate of naturalization number:

Certificate of Naturalization Is Lost, Stolen, or Damaged Beyond Repair

Applying for a replacement is a common solution to the above reasons. However, when submitting Form N-565, the applicant must provide specific proof of the stolen, lost, or destroyed document. Generally, this involves producing a police report and a sworn statement as evidence. Based on the information provided, the USCIS will process and evaluate your application.

Needing to Change the Document Due to a USCIS Error

There can be instances where the USCIS has made an error on your document or needs to update some information. For example, if the applicant supplied faulty data, the applicant must fill out Form N-565 and pay the fee.

Changes can come in the form of a name change, gender change, or any typological error made by the USCIS.

Obtaining a name change requires a certified copy of a court order or a marriage/divorce certificate. For a gender change, the applicant needs a certified copy of a court order, medical certification by a licensed physician, certified copy of an amended birth certificate, or any other official documentation that recognizes the gender change or the new gender issued by the United States of America, local jurisdictions, or a foreign state. Applicants can also supply a passport and driver’s license.

It is important to note that applicants cannot change the date of birth on the naturalization certificate if entered incorrectly in Form N-400. Later in the process, they have to swear to have the same date of birth during the interviews and the swearing-in ceremony. Such instances are extremely rare and require the assistance of an immigration attorney.

When Can I Expect This Process to Finish?

The overall time taken by the USCIS to process a replacement application is approximately one year, but in some cases, it can get done quickly. However, it is worth noting that the USCIS processing times for replacing a C-file number are generally quite long.

To reduce the overall time taken in the application process, it is advisable to prepare another N-565 application package with complete details of the applicant. Furthermore, it is recommended that all required documentation and evidence be set aside in this application package. There are immigration lawyers, pro bono law firms, and online resources that help individuals prepare and organize their applications.

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The certificate of naturalization number is an essential numeric identity for any naturalized citizen of the United States of America. As we’ve seen above, this number is useful in a variety of scenarios and, therefore, should be kept safe. For more information, contact an immigration lawyer or visit the USCIS website.

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Frank Gogol

I’m a firm believer that information is the key to financial freedom. On the Stilt Blog, I write about the complex topics — like finance, immigration, and technology — to help immigrants make the most of their lives in the U.S. Our content and brand have been featured in Forbes, TechCrunch, VentureBeat, and more.

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