Quick Answer: What Is a Certificate of Citizenship?
A Certificate of Citizenship is a document issued by U.S. Citizenship and Immigration Services (USCIS) as official evidence of U.S. citizenship. It is generally used by someone who has already acquired citizenship through a U.S. citizen parent, either at birth or automatically after birth when the legal requirements were met.
The certificate does not grant or create citizenship. Form N-600 is generally used to request a Certificate of Citizenship for someone who is already a U.S. citizen. Certain qualifying children living outside the United States may instead use Form N-600K.
A Certificate of Citizenship is not required for every person who acquired citizenship through a parent. A valid U.S. passport may also serve as evidence of citizenship. Once issued, a Certificate of Citizenship does not expire.
Last verified: September 2026 | Official source: USCIS Form N-600
Who Can Get a Certificate of Citizenship?
A Certificate of Citizenship generally documents U.S. citizenship acquired through one or both U.S. citizen parents. For Form N-600, citizenship may have been acquired at birth or automatically after birth, depending on the law and facts that applied at the time.
Citizenship Acquired at Birth
Some people born outside the United States acquire U.S. citizenship at birth through one or both U.S. citizen parents. Whether citizenship was acquired depends on factors such as the person’s date of birth, the parent’s citizenship, the parent-child relationship, and the citizenship law in effect at that time.
Citizenship Automatically Acquired After Birth
Some children automatically acquire U.S. citizenship after birth when the applicable legal requirements are met. Qualifying adopted children may also acquire citizenship under the rules that apply to their circumstances.
Adults can request a Certificate of Citizenship later if they acquired citizenship earlier but never obtained USCIS documentation of that status.
For detailed rules involving date of birth, parentage, age, residence, custody, adoption, and other requirements, see our Form N-600 eligibility and requirements guide.
Do You Need a Certificate of Citizenship?
No. Not everyone who acquired U.S. citizenship through a parent is required to obtain a Certificate of Citizenship. It provides permanent USCIS-issued documentation of citizenship already acquired.
A valid U.S. passport can also serve as evidence of U.S. citizenship. A person born abroad may also have a Consular Report of Birth Abroad (CRBA), depending on how their citizenship was documented.
Someone may still choose to obtain a Certificate of Citizenship when they want permanent USCIS documentation of their citizenship status.
How Do You Get a Certificate of Citizenship?
To get a Certificate of Citizenship, first confirm that you have already acquired U.S. citizenship through a U.S. citizen parent. The form and evidence you need depend on how and when citizenship was acquired.
For most people seeking USCIS documentation of citizenship already acquired, Form N-600, Application for Certificate of Citizenship, is the appropriate form.
| Step | What to do |
|---|---|
| Confirm citizenship | Determine whether citizenship was acquired at birth or automatically after birth. |
| Choose the correct form | Use Form N-600 to document citizenship already acquired, or Form N-600K when the separate requirements for certain children abroad apply. |
| Prepare evidence | Gather documents that support the applicable citizenship claim. |
| File the application | Follow the current USCIS filing method and instructions. |
| USCIS review | USCIS reviews the application and, if approved, issues the certificate after any required oath is completed or waived. |
For the complete application process, see our Form N-600 guide. For a specific step, see our Form N-600 eligibility and requirements, Form N-600 document checklist, Form N-600 instructions, Form N-600 filing fee, or Form N-600 processing time guides.
Need Help Preparing Form N-600?
ImmigrationDirect can help you check whether Form N-600 may apply based on the information you provide. If eligible, you can continue with guided form preparation, organize the information needed for your application, and review your answers for missing or inconsistent details.
Any eligibility assessment is based on your responses. USCIS makes the final eligibility determination and decision.
Form N-600 or Form N-600K?
Form N-600 is generally used by someone who has already acquired U.S. citizenship and wants a Certificate of Citizenship as official documentation.
Form N-600K serves a different purpose. It is used under INA 322 for certain qualifying children who live outside the United States and are seeking citizenship and a Certificate of Citizenship through a U.S. citizen parent.
The correct form depends on whether citizenship was already acquired and the applicant’s circumstances.
What Can a Certificate of Citizenship Be Used For?
A Certificate of Citizenship can be used as official evidence of U.S. citizenship when proof of citizenship is required. It does not create citizenship or give someone new rights; it documents citizenship that has already been acquired.
Common uses include:
- Applying for a U.S. passport. The U.S. Department of State accepts a Certificate of Citizenship as primary evidence of U.S. citizenship.
- Providing proof to a government agency when citizenship documentation is requested for a specific purpose.
- Supporting certain immigration matters, such as showing U.S. citizenship when petitioning for a qualifying family member.
- Maintaining USCIS-issued documentation of citizenship. The certificate can provide documentary evidence of citizenship when proof is required.
The exact document required can depend on the agency or process requesting proof of citizenship.
Certificate of Citizenship vs. U.S. Passport vs. CRBA
A Certificate of Citizenship, U.S. passport, and Consular Report of Birth Abroad (CRBA) can all provide evidence of U.S. citizenship, but they serve different purposes and are issued by different government agencies.
A Certificate of Citizenship is USCIS-issued proof of citizenship already acquired under U.S. citizenship law. A U.S. passport also serves as citizenship evidence and is used for international travel. A CRBA documents that a person born outside the United States acquired U.S. citizenship at birth.
| Document | What it documents | Issuing agency |
|---|---|---|
| Certificate of Citizenship | Citizenship already acquired under applicable U.S. citizenship law | USCIS |
| U.S. passport | Evidence of U.S. citizenship and an international travel document | U.S. Department of State |
| Consular Report of Birth Abroad (CRBA) | U.S. citizenship acquired at birth outside the United States | U.S. Department of State |
For more information about citizenship documented at birth abroad, see our Consular Report of Birth Abroad (CRBA) guide.
Certificate of Citizenship vs. Certificate of Naturalization
A Certificate of Citizenship and a Certificate of Naturalization both serve as official evidence of U.S. citizenship, but they document citizenship obtained in different ways.
A Certificate of Citizenship generally documents citizenship that a person already acquired under U.S. citizenship law, often through one or both U.S. citizen parents. A Certificate of Naturalization is issued to someone who becomes a U.S. citizen through the naturalization process.
| Document | What it shows |
|---|---|
| Certificate of Citizenship | Citizenship already acquired under applicable U.S. citizenship law |
| Certificate of Naturalization | Citizenship obtained through the naturalization process |
For a detailed comparison, see our Certificate of Citizenship vs. Certificate of Naturalization guide.
Does a Certificate of Citizenship Expire?
No. A Certificate of Citizenship does not expire. Once issued, it remains permanent evidence of the U.S. citizenship that the person already acquired.
A new certificate may be needed if the original is lost, stolen, damaged, or requires an eligible correction. This is a replacement or correction process, not a renewal. Certificate holders do not need to renew the document periodically simply because time has passed.
Certificate of Citizenship Number: What Is It and Where Is It Used?
A Certificate of Citizenship Number is the unique number assigned to a Certificate of Citizenship. It is different from the certificate holder’s Alien Registration Number (A-Number) and from a USCIS Online Account Number.
Some USCIS forms may ask for the Certificate of Citizenship Number when a person is using the certificate as proof of U.S. citizenship. Those forms may also request the place of issuance and date of issuance shown on the certificate. USCIS forms list the Certificate of Citizenship Number and A-Number as separate fields.
When a form asks for the citizenship certificate number, copy it exactly as it appears on the Certificate of Citizenship.
How Do You Replace or Correct a Certificate of Citizenship?
If USCIS previously issued you a Certificate of Citizenship and it was lost, stolen, damaged, or needs an eligible correction, you may use Form N-565, Application for Replacement Naturalization/Citizenship Document, to request a replacement or corrected certificate.
Form N-565 serves a different purpose from Form N-600:
- Form N-600 is generally used to request an initial Certificate of Citizenship based on citizenship already acquired.
- Form N-565 is used to replace or correct certain citizenship or naturalization documents that USCIS previously issued.
For detailed replacement and correction requirements, see our Form N-565 guide.
Need help preparing Form N-565? ImmigrationDirect can guide you through the application, help organize the information you provide, and review your responses for missing or inconsistent details before filing. Start Your Form N-565
Need a Certificate of Citizenship?
If you believe you already acquired U.S. citizenship and want USCIS documentation of that status, ImmigrationDirect can help you check whether Form N-600 may apply based on the information you provide. You can then continue with guided preparation, organize the required information, review your responses for missing or inconsistent details, and follow filing instructions.
ImmigrationDirect is not USCIS. USCIS makes the final eligibility determination and decision, and no preparation service can guarantee approval.
