There are five established ways to get citizenship in another country: through ancestry, by being born on its soil, by marrying a citizen, by living there long enough to naturalize, or by making a qualifying investment. Which one fits you depends on your family history, where you were born, who you’re married to, how patient you are, and how much money you’re willing to put on the table. Each path has its own eligibility rules, documentation demands, and timelines, and each has consequences for your current citizenship, your taxes, and your future obligations that are worth understanding before you commit.
Claiming Citizenship Through Ancestry
If a parent, grandparent, or in some cases a more distant ancestor held citizenship in a country, you may be able to claim that same citizenship through bloodline. The Latin term for this is jus sanguinis, and it exists specifically to let diaspora communities maintain legal ties to their ancestral homeland. Countries offering it include Ireland (through grandparents, and sometimes great-grandparents if the chain was registered), Italy (historically with no generational limit, though recent reforms tightened eligibility), Poland, Hungary, Germany, Greece, and the United Kingdom (generally limited to parents).
The practical challenge is documentation. You need to build a paper trail proving an unbroken chain of citizenship from your ancestor to you: birth certificates, marriage records, naturalization documents, and sometimes death certificates for every link. If your ancestor became a citizen of another country before your parent was born, the chain may be broken and your claim fails. Italy’s 2025 reform, for instance, now requires a more direct connection to Italy than previous rules demanded, cutting off many claims that would have succeeded a few years earlier.
Start by contacting the relevant consulate. They’ll tell you which documents you need, how far back the law reaches, and whether your specific situation qualifies. Even after you’ve assembled everything, expect one to three years of processing time, because consulates handle ancestry claims alongside their regular workload.
Birthright Citizenship
Some countries grant citizenship automatically to anyone born on their soil, regardless of the parents’ nationality. This principle, called jus soli, is most common in the Americas. The United States, Canada, Brazil, Mexico, and most Caribbean and Central American nations follow some version of it. Outside the Western Hemisphere, unconditional birthright citizenship is rare.
Several countries apply a conditional version, where birth on the territory only triggers citizenship if at least one parent already has legal residency or permanent status there. If you were born in a country with birthright citizenship and never claimed it, contact that country’s consulate to find out whether you’re already a citizen on paper or need to go through a formal recognition process.
Citizenship Through Marriage
Marrying a citizen of another country usually opens a faster track than standard naturalization. Most countries require you to live together in a genuine marriage for a set period, often three to five years, before you can apply. In the United States, a spouse of a U.S. citizen can apply for naturalization after three years of continuous residence rather than the usual five, as long as the couple has lived together in marital union for that entire period.1U.S. Citizenship and Immigration Services. I am Married to a U.S. Citizen
Immigration authorities scrutinize marriage-based applications heavily to screen out sham marriages. Expect questions about your daily life together, joint financial accounts, shared leases, and other evidence that the relationship is real. Some countries conduct home visits or separate interviews where each spouse answers the same questions independently. Inconsistent answers raise red flags that can derail your application.
Naturalizing After Long-Term Residency
The most common route is simply living in a country long enough on a valid residence permit, then applying to naturalize. Most countries require somewhere between five and ten years of continuous legal residence before you’re eligible. The United States requires five years of continuous residence after becoming a lawful permanent resident, with physical presence in the country for at least half that time.2Office of the Law Revision Counsel. 8 USC 1427 – Requirements of Naturalization Germany requires eight years, reducible to six with a completed integration course. Portugal traditionally required five years, though recent changes may extend that timeline for certain applicants.
“Continuous residence” doesn’t mean you can never leave, but extended absences create problems. In the U.S., any trip abroad lasting six months or more is presumed to break continuous residence, and you’d need evidence of ongoing ties like tax filings, mortgage payments, and employment to overcome that presumption.3U.S. Citizenship and Immigration Services. USCIS Policy Manual Volume 12 Part D Chapter 3 – Continuous Residence The principle is the same everywhere: the country wants proof you’ve genuinely made it your home, not just maintained a mailing address there.
During the residency period, you’re expected to obey local laws, pay taxes, and integrate into the community. A criminal conviction during this window can disqualify you or reset the clock entirely. Financial self-sufficiency also matters. Countries want assurance you can support yourself, which typically means showing bank statements, employment contracts, or tax returns proving stable income.4Canada.ca. Proof of Funds
Citizenship by Investment
A handful of countries sell a faster path in exchange for a significant financial contribution. Caribbean nations dominate this space. Dominica’s program starts at $200,000 for a donation to its economic diversification fund. Grenada requires $235,000 for a single applicant or family of four. Antigua and Barbuda sets its threshold at $230,000 for a family, and St. Kitts and Nevis charges $250,000 through its sustainability contribution route. Real estate options exist at higher price points, typically $325,000 and up, with mandatory holding periods of several years.
European options are pricier and slower. Portugal’s golden visa requires a minimum €500,000 investment into qualifying funds or scientific research (real estate was removed as an option in 2023), and the path to citizenship still takes at least five years of residency. The U.S. EB-5 program requires $800,000 in a targeted employment area or $1.05 million elsewhere, and it grants a green card rather than immediate citizenship, meaning you’d still need to go through the standard naturalization process afterward.5U.S. Citizenship and Immigration Services. EB-5 Immigrant Investor Program
Investment programs attract intense scrutiny: thorough background checks, source-of-funds verification, and due diligence that can take months. They also face political pressure and change frequently. Several Caribbean nations have raised their minimums recently, and the EU has pushed member states to tighten or close their programs. Verify current requirements directly with the country’s official immigration authority before committing money.
Language, Civics, and Background Checks
Almost every country that offers naturalization requires you to demonstrate some level of proficiency in the national language. In Europe, most countries peg their requirement to the Common European Framework of Reference for Languages (CEFR), a standardized scale from A1 (beginner) to C2 (fully proficient). The bar for citizenship typically falls between A2 and B2. Portugal and Spain require A2, which covers basic conversational ability. Germany, France, Austria, Finland, and Denmark require B1 or higher, meaning you need to handle everyday conversations, write simple texts, and understand the main points of clear standard speech.
In the United States, the naturalization interview itself serves as the English test. A USCIS officer evaluates your ability to read, write, and speak basic English during the interview, and you also take an oral civics test covering U.S. history and government. The current version consists of 20 questions drawn from a list of 128, and you need at least 12 correct to pass.6U.S. Citizenship and Immigration Services. Study for the Test Many other countries have their own versions of civic knowledge tests covering the constitution, national holidays, and basic rights and responsibilities.
Every naturalization process also includes a criminal background check. You’ll typically need police clearance certificates from your home country and any other country where you’ve lived for a significant period. In the U.S., USCIS collects fingerprints and runs them through the FBI’s database as part of the standard process.7U.S. Citizenship and Immigration Services. USCIS Policy Manual Volume 12 Part B Chapter 2 – Background and Security Checks If you’re a U.S. citizen applying elsewhere, you can request an FBI Identity History Summary, which other countries commonly accept as proof of a clean record.8U.S. Department of State. Criminal Records Checks Plan ahead, because obtaining police clearances from multiple countries can take weeks or months.
Documents You’ll Need
Regardless of which path you take, the paperwork shares a common core. You’ll need your current passport, birth certificate, and marriage certificate (if applicable), all in original or certified form issued by a government registry. Most countries also require proof of residency such as lease agreements, utility bills, or mortgage statements. For marriage-based applications, expect to provide evidence of your shared life: joint bank accounts, tax returns filed together, and similar documentation.9U.S. Citizenship and Immigration Services. U.S. Citizenship and Immigration Services Document Checklist
Any document issued in a language other than the country’s official language will need a certified translation. In the U.S., this means a translation accompanied by a signed certificate of accuracy stating the translator is competent and the translation is complete. Other countries have their own standards, sometimes requiring translations by a sworn or court-certified translator. Check the requirements before paying for a translation that might not be accepted.
Apostilles and Authentication
Documents issued in one country often need to be authenticated before another country will accept them. For countries that belong to the Hague Apostille Convention, which now includes over 125 nations, authentication is handled through a single apostille certificate issued by a designated authority in the country where the document originates.10HCCH. Apostille Section If the destination country isn’t a member, you may need to go through a multi-step authentication process involving your country’s foreign affairs ministry and the destination country’s consulate.11USAGov. Authenticate an Official Document for Use Outside the U.S.
Can You Keep Your Current Citizenship?
Whether you can keep your original citizenship after acquiring a new one depends entirely on the laws of both countries involved. Many countries freely permit dual citizenship, including the United States, the United Kingdom, Canada, France, Australia, and most of Latin America. But a significant number do not.
China, Japan, Singapore, India, and most Gulf states prohibit dual citizenship outright. Japan requires citizens to choose one nationality by age 22. India doesn’t allow dual citizenship at all but offers a separate Overseas Citizen of India status that provides some rights without full citizenship. Within the EU, Austria, Estonia, the Netherlands, Slovakia, Spain, and several others may withdraw citizenship if you voluntarily acquire another nationality, though exceptions often apply for citizens who acquired dual status at birth or through marriage.12European Parliament. Acquisition and Loss of Citizenship in EU Member States
This is the area where people make the most expensive mistakes. If your home country doesn’t allow dual citizenship and you acquire a new one without checking first, you could lose your original citizenship automatically. Before you apply anywhere, confirm the rules on both sides: whether the new country requires you to renounce your current citizenship, and whether your current country will revoke it if you don’t.
Practical Consequences of Holding Two
Each country generally treats you as its own citizen while you’re within its borders. If you’re a dual U.S.-French citizen standing on French soil, France considers you French and doesn’t recognize the United States as having a role in your legal affairs there. The practical consequence: if you get into legal trouble in one of your countries of citizenship, your other country’s embassy may not be able to help you. The U.S. State Department acknowledges that while its policy is to provide consular services to all U.S. citizens regardless of dual status, a dual national in their other country of citizenship may find that the host country refuses to let U.S. officials intervene.13U.S. Department of State. 7 FAM 080 – Dual Nationality
Most countries also require their citizens to enter and exit on that country’s passport. The United States requires U.S. citizens to use a U.S. passport to enter and leave the country.14U.S. Department of State. Dual Nationality As a dual citizen, you’ll generally carry both passports when traveling and use whichever one the country you’re entering expects to see. When traveling to a third country where you hold neither citizenship, you can choose whichever passport offers easier entry.
Tax Consequences of a Second Citizenship
This is where acquiring a second citizenship gets complicated in ways most people don’t anticipate. Tax obligations don’t follow your passport; they follow the rules of each country that claims you as a tax resident or citizen. And the United States is unique among major countries in taxing its citizens on worldwide income regardless of where they live.
If You’re a U.S. Citizen Living Abroad
U.S. citizens who become citizens of another country and move there still owe U.S. taxes on their global income. You must file a U.S. tax return every year, reporting income from all sources worldwide, just as you would if you lived in the United States.15IRS. U.S. Citizens and Residents Abroad – Filing Requirements The foreign earned income exclusion allows you to exclude up to $132,900 (for 2026) of foreign earnings from U.S. tax, and foreign tax credits can offset double taxation, but neither eliminates the filing requirement itself.16IRS. Figuring the Foreign Earned Income Exclusion
On top of income taxes, two separate reporting requirements apply to foreign financial accounts. If the combined value of your foreign bank and investment accounts exceeds $10,000 at any point during the year, you must file a Report of Foreign Bank and Financial Accounts (FBAR) with FinCEN.17FinCEN. Report Foreign Bank and Financial Accounts Separately, if the total value of your foreign financial assets exceeds $200,000 on the last day of the tax year (or $300,000 at any point during the year) while living abroad, you must file Form 8938 under FATCA. The thresholds are higher for joint filers: $400,000 on the last day of the year or $600,000 at any point.18IRS. Do I Need to File Form 8938, Statement of Specified Foreign Financial Assets Penalties for failing to file these forms are severe and can include substantial civil fines.19IRS. Report of Foreign Bank and Financial Accounts (FBAR)
If You Renounce U.S. Citizenship
Some dual citizens decide to renounce U.S. citizenship to escape worldwide taxation. This triggers its own set of tax consequences. Under the expatriation tax provisions of the Internal Revenue Code, if you qualify as a “covered expatriate,” all your worldwide assets are treated as if you sold them the day before you renounced. Any unrealized gain above a $600,000 exclusion is taxed immediately.20Office of the Law Revision Counsel. 26 USC 877A – Tax Responsibilities of Expatriation You qualify as a covered expatriate if your net worth exceeds $2 million, your average annual net income tax over the five preceding years exceeds a set threshold, or you can’t certify that you’ve been compliant with all federal tax obligations for the preceding five years. Renouncing is permanent and irreversible, so the tax math needs to be worked out carefully with a qualified professional beforehand.
Obligations in the New Country
Your new country of citizenship will have its own tax rules. Most countries tax residents on worldwide income, though they generally don’t tax non-resident citizens the way the United States does. When you become a tax resident of a new country, you’ll need to understand its income tax rates, filing deadlines, and any tax treaties it has with your home country that prevent double taxation. Failing to file in either country can result in penalties, interest, and problems with future citizenship or residency renewals.
Other Obligations That Come With a New Passport
Citizenship isn’t just a passport. It comes with legal obligations that vary by country. Many nations require citizens to vote (Australia and Belgium impose fines for not voting), serve on juries, or register for military service. U.S. dual nationals must register with the Selective Service System within 30 days of turning 18, regardless of where they live.21Selective Service System. Who Needs to Register Some countries with mandatory military service, like South Korea and Israel, may require dual citizens to serve even if they grew up abroad. Research the specific obligations of your new country before you finalize your application, because you’re agreeing to all of them when you take the oath.
Why Applications Get Denied
Understanding why applications fail helps you avoid the same traps. The most common reasons for denial:
- Criminal history. A serious conviction can be a permanent bar. In the U.S., an aggravated felony conviction after November 29, 1990, creates a permanent statutory bar to naturalization. Less serious offenses involving dishonesty or violence may create temporary bars during the review period.22U.S. Citizenship and Immigration Services. Important Notice Concerning Denial of Citizenship
- Gaps in residency. Spending too much time outside the country during the required residency period is one of the easiest ways to disqualify yourself, and many applicants don’t realize it until the interview.
- Failed language or civics tests. Most countries give you a second chance, but repeated failures delay your application by months or longer.
- Incomplete or inconsistent documentation. Discrepancies between your application and supporting documents, missing translations, or unsigned forms can result in outright rejection.
- Inability to show financial self-sufficiency. If the country’s immigration authority believes you can’t support yourself, it can deny your application regardless of how long you’ve lived there.
The good moral character determination in U.S. naturalization is more nuanced than a simple pass/fail on criminal history. USCIS looks at the totality of the evidence, weighing negative factors like prior convictions against positive factors like community involvement, employment history, and family ties. Other countries apply similar holistic evaluations, even if they don’t use the same terminology. Choose the path that fits your situation, verify current rules with the country’s official immigration authority before you spend money, and give yourself a longer runway than you think you need.