What Is a Certificate of Naturalization?
A Certificate of Naturalization is an official USCIS document showing that a person became a U.S. citizen through naturalization. The initial certificate issued after naturalization is Form N-550.
USCIS issues the certificate after an approved naturalization applicant takes the Oath of Allegiance. A person does not become a U.S. citizen until the oath is completed. The certificate can then be used as evidence of U.S. citizenship for purposes such as applying for a U.S. passport or updating government records.
Last reviewed against USCIS and U.S. Department of State guidance: September 17, 2026.
Who Receives a Certificate of Naturalization?
Most applicants naturalize after becoming lawful permanent residents and filing Form N-400, Application for Naturalization. However, the exact naturalization requirements vary depending on the applicant’s legal basis, including special provisions for qualifying military service.
During the process, USCIS reviews the application, collects biometrics when required, conducts the naturalization interview and applicable English and civics testing, and makes a decision on the application. After approval and completion of the oath, the new citizen receives the Certificate of Naturalization.
Planning to apply for naturalization? Review the Form N-400 eligibility requirements before preparing your citizenship application.
What Is a Certificate of Naturalization Used For?
A Certificate of Naturalization is evidence of U.S. citizenship. You may use it when an agency, organization, or government process requires proof that you became a U.S. citizen through naturalization.
Common uses are:
- U.S. passport application: Accepted by the Department of State as primary evidence of U.S. citizenship
- Social Security records: Can be used to update your citizenship status with the Social Security Administration
- Family immigration: May serve as evidence that a petitioner is a U.S. citizen when citizenship documentation is required
- Government records or benefits: May be accepted when an agency requires evidence of U.S. citizenship
- Use with foreign governments: A certified true copy may be needed when a foreign authority requires authenticated proof of naturalization
The Department of State currently lists a Certificate of Naturalization as primary citizenship evidence for passport applications.
Certificate of Naturalization vs. Certificate of Citizenship
| Certificate of Naturalization | Certificate of Citizenship | |
|---|---|---|
| How citizenship is obtained | Through naturalization | Generally acquired or derived through a qualifying U.S. citizen parent |
| Initial certificate | Form N-550 | Form N-560 |
| Related application | Form N-400 for most naturalization applicants | Form N-600 to request documentation of citizenship |
These documents both provide evidence of U.S. citizenship, but they document different paths to citizenship. See our Certificate of Naturalization vs. Certificate of Citizenship guide for the full comparison.
Certificate of Naturalization vs. U.S. Passport
| Certificate of Naturalization | U.S. Passport | |
|---|---|---|
| Issued by | USCIS | U.S. Department of State |
| Evidence of U.S. citizenship | Yes | Yes |
| International travel document | No | Yes |
| Routine expiration | No | Yes |
| Typical role | Record/evidence of naturalization and citizenship | Travel, identification and citizenship evidence |
A Certificate of Naturalization is one type of primary citizenship evidence accepted for a passport application, but it is not the only qualifying citizenship document.
Depending on the applicant’s circumstances, the Department of State also accepts documents such as a qualifying U.S. passport, Consular Report of Birth Abroad, or Certificate of Citizenship.
What Does a Certificate of Naturalization Look Like?
USCIS has issued different versions of the Certificate of Naturalization over time, so the exact layout and security features can vary by issuance date.
Current certificates include security features designed to make alteration and counterfeiting more difficult. USCIS has described newer versions as including an embedded digitized photograph and signature, a color-shifting background, and other enhanced security features. Previously issued valid certificates remain valid.
Depending on the version, the certificate contains identifying information about the naturalized citizen, certificate identifiers, a photograph and signature, and information relating to the person’s naturalization.
Where Is the Certificate of Naturalization Number?
The Certificate of Naturalization number is typically located in the upper-right area of the certificate. USCIS describes Naturalization/Citizenship Certificate Numbers as alphanumeric identifiers containing at least six characters.
Because USCIS has issued different certificate versions, do not assume that every Certificate of Naturalization has an eight-character number or that the number always appears in the same color.
Certificate Number vs. A-Number: What Is the Difference?
| Certificate number | A-Number | |
|---|---|---|
| What it identifies | The Certificate of Naturalization document | The person’s USCIS immigration record |
| Same number? | No | No |
| Where it may appear | Typically in the upper-right area of the certificate | May appear separately on USCIS documents and the certificate |
| Used for | Identifying the naturalization certificate | Identifying the person’s immigration record |
If a form asks specifically for the Certificate Number, do not automatically enter your A-Number. Follow the instructions for the form you are completing.
Form N-550 vs. Form N-570
Both N-550 and N-570 are Certificates of Naturalization, but they represent different document designations.
| Document | What it means |
|---|---|
| Form N-550 | Initial Certificate of Naturalization issued after a person completes naturalization |
| Form N-570 | Replacement Certificate of Naturalization issued when USCIS approves an eligible replacement request |
How to Store Your Certificate of Naturalization
Keep your original Certificate of Naturalization in a secure, dry location where it is protected from loss, water, tearing, or other damage. Avoid altering or marking the document in a way that could obscure its information or security features.
You may keep a clear photocopy or secure digital scan for your records. However, a copy may not replace the original when an agency requires original citizenship evidence.
What If Your Certificate of Naturalization Is Lost or Damaged?
If your Certificate of Naturalization is lost, stolen, destroyed, or mutilated, you may request a replacement from USCIS by filing Form N-565, Application for Replacement Naturalization/Citizenship Document.
Form N-565 is also used for certain corrections or updates to naturalization documents. See our Certificate of Naturalization replacement guide for the filing requirements, documents, fees, and processing information.
How Do I Get a Certified True Copy of My Certificate of Naturalization?
A certified true copy is a copy of your Certificate of Naturalization that USCIS has compared with the original and certified as a true copy. This may be needed when your naturalization document must later be authenticated for official use abroad.
USCIS guidance says you should bring:
- Your original Certificate of Naturalization;
- A photocopy of the certificate; and
- A valid photo ID.
Contact USCIS to request the appropriate appointment or service. USCIS’s current appointment system allows certain appointment requests online and directs users to the USCIS Contact Center when the needed service cannot be handled through the online tools.
If the certified copy will be used abroad, check the U.S. Department of State’s current authentication requirements for the destination country.
Certificate of Naturalization FAQs
Does a Certificate of Naturalization expire?
No. A Certificate of Naturalization does not have a routine expiration date. USCIS has issued different certificate versions over time, and previously issued valid certificates remain valid.
Will I get my Certificate of Naturalization back after applying for a U.S. passport?
Yes. If you submit your Certificate of Naturalization as citizenship evidence for a passport application, the Department of State returns your supporting documents by mail, generally separately from the passport.
Can I use a Certificate of Naturalization for Form I-9?
Not under the current Form I-9 Lists of Acceptable Documents. Employees must present either one acceptable List A document or a combination of one acceptable List B document and one acceptable List C document. The current I-9 list does not specifically list a Certificate of Naturalization as an acceptable document.
Need Help With Your Next Citizenship Step?
If you have not yet become a U.S. citizen, ImmigrationDirect can help you prepare Form N-400 through guided questions, step-by-step support, and a review for missing or inconsistent information before filing.
Already naturalized but need to replace a lost, damaged, or incorrect Certificate of Naturalization? Review the Form N-565 requirements, documents, fees, and filing steps before requesting a replacement.
ImmigrationDirect is a private company and is not affiliated with USCIS. USCIS determines eligibility and makes all final decisions on naturalization and replacement-document applications.
