A second passport looks like a purchase. You meet the conditions, pay, receive the document, and the deal feels done.
The obligations attached to citizenship arrive later. Many of them take effect by operation of law, reach your children as readily as you, and only become visible once the moment to act on them has passed.
The rules below span descent, dual nationality, military service, naming, tax, and revocation. None is exotic, and most are already law somewhere a mobile family is likely to hold or claim a passport. Here are 11 that people meet too late.
1. Citizenship by descent comes with filing deadlines
A bloodline claim feels like a birthright that waits for you. It does not always wait.
Italy is the sharpest recent example. Under Law 74/2025, a descendant keeps the old broad route through an Italian ancestor only if, by 11:59 p.m. Rome time on March 27, 2025, they had filed an application with a consulate or comune, had received notice of an appointment from the competent office, or already had a claim before a court. Everyone else lost that broad route on that date, though narrower openings survive.
The Constitutional Court rejected the main challenge to the reform in March 2026 and set out its reasoning in a judgment deposited on April 30, so the reform stands for now. Two questions remain open.
The Court left open the position of applicants who had begun the process but held no appointment by the cutoff, which is the live question for anyone caught mid-application, and it referred the underlying EU law question to the Court of Justice of the European Union in July 2026, a reference that usually takes more than a year to answer, with a separate question on the older 1912 nationality law still before Italy’s Court of Cassation.
Timing controls transmission even where no political deadline exists. Irish citizenship through a grandparent runs through the Foreign Births Register, and you become an Irish citizen only from the date your birth is entered on it, not from your birth. The Irish government states plainly that if a parent is not on the register when their child is born, the child has no entitlement. Registration currently takes around a year, so a parent who starts late can lock a child out permanently.
Aran Hawker, co-founder of CIP Turkey, puts the practical point simply. “If you have a claim through a bloodline, look into it as early as you can,” he says. “There are time limits on these routes, and the opportunity does not stay open just because the ancestry does.”
A bloodline claim is a clock, not a guarantee.
2. Bloodlines run out at a generation limit
Many people assume citizenship by descent passes down forever. Most countries cut it off somewhere.
Italy now recognizes a claim mainly where a parent or grandparent held, or held at death, only Italian citizenship, or where a qualifying parent lived in Italy for at least two consecutive years after acquiring Italian citizenship and before the applicant’s birth. A distant ancestor alone no longer carries a claim.
The limit sits in a different place in every country. In Ireland you can claim through a grandparent, and through a great-grandparent only if your parent registered before you were born. Slovakia and Bulgaria reach the third generation, though both run as facilitated naturalization rather than automatic recognition. In July 2026, Slovakia went further, dropping the residence condition for descendants of Czechoslovak citizens born on its territory.
Some countries move the other way. Canada removed its first-generation limit when Bill C-3 took effect in December 2025, so a Canadian parent can now pass citizenship beyond the first generation, though a child born abroad after that date past the first generation qualifies only if the Canadian parent spent at least 1,095 days in Canada before the birth. Check where your specific line runs out before you count on it, because the answer changes by country and by year.
3. Some countries make you give up the passport you have
Countries split on whether they permit dual citizenship, and naturalizing in one that does not means surrendering what you already hold.
Austria naturalizes an applicant only after they have taken every possible step to release their existing citizenship, unless Austria grants advance permission to keep it. India and Singapore do not recognize dual citizenship at all, so acquiring either passport means giving up your current one. The requirement also shifts over time; Germany made most applicants surrender their prior citizenship until it lifted that condition in June 2024.
Hawker treats the decision as a straight comparison between the two documents. “Look at what you are actually giving up,” he says. “If the passport you would surrender is much weaker than the one you are gaining, the trade is not really a loss. If it is not, then you are paying a genuine price, and you should know that going in.”
The risk lives in the sequencing. Some frameworks make you release a secure citizenship before or shortly after the new one is confirmed, which can briefly leave you exposed if the timing slips, and a renunciation you complete is rarely easy to reverse if the new grant falls through.
4. Others cancel your old citizenship the moment you take a new one
Even where you never intend to give up your original nationality, some countries take it from you automatically the instant you acquire another.
China is the widest-reaching case. Under Article 9 of its Nationality Law, a Chinese national who has settled abroad and voluntarily acquires a foreign nationality automatically loses Chinese nationality. There is no application and no notice. The loss happens by operation of law the moment you naturalize elsewhere.
Japan’s Article 11 works the same way, and its Supreme Court has upheld the rule; a Japanese national who voluntarily takes a foreign nationality loses Japanese nationality. Austria strips citizenship automatically from anyone who voluntarily acquires a foreign one without securing a retention permit first. Germany sat in this category until recently.
Section 25 of its Nationality Act stripped citizenship from anyone who acquired another without a retention permit first, until the 2024 modernization act abolished both on June 27 of that year.
The danger is silent. Enforcement can lag for years while you keep using the old passport, but the legal status is already gone, which tends to surface when you try to renew it or pass it to a child. Confirm whether your home country treats a new passport as automatic grounds for losing the old one before you apply.
5. A second passport can make you eligible for the draft
A citizenship you inherited or acquired can carry a military obligation you never signed up for, and it can attach to your sons.
South Korea is the clearest illustration. Every male citizen, including a dual national who has never lived in Korea, is liable for military service. A male dual national must renounce Korean nationality by March 31 of the year he turns 18. Miss that date and he generally cannot give up Korean citizenship until he completes service or qualifies for an exemption, which can mean waiting into his late thirties.
Because the rule draws little attention abroad, families often discover it only when a foreign-born son is treated as a Korean conscript. Chun Jong-Joon, a Washington-based immigration attorney, told the Los Angeles Times that around 250,000 diaspora Koreans hold Korean nationality without realizing it.
Greece, Turkey, and Israel also conscript citizens and can reach dual nationals in some circumstances, with their own rules on deferral and, in Turkey’s case, a paid exemption.
Hawker, who has faced conscription personally, treats it as a reason to look elsewhere. “I was not willing to serve, and I would not expect many people to be, unless they have real family ties to the country,” he says. “If there is another route to the same outcome, take the other route.”
Greece has narrowed the exit its diaspora relied on. Under Law 5265/2026, in force from January 2026, a Greek man counts as permanently resident abroad, and so defers service indefinitely, only if he lived outside Greece across the window the law now sets, from the start of the year he enters his sixteenth year to the end of the year he turns 18, and he forfeits the status by spending more than six months in Greece in any calendar year.
Anyone relying on the looser previous test has until the end of 2028 to opt into the old rules. Before claiming a citizenship for a child, check whether it comes with a service liability and at what age it starts.
6. A new nationality can change your legal name
A passport has to render your name in a fixed way, and a new citizenship can hand you a spelling, or a structure, you did not choose.
Countries issue travel documents in Latin script under a shared international standard, and the issuing authority decides the official transliteration of a name written in Arabic, Chinese, Cyrillic, or another script. That transliterated form becomes your name of record, and it may not match how you spell it on your other documents. Mismatched names across passports, bank records, property titles, and inheritance papers create real friction, from blocked transactions to questions at the border.
Hawker sees the consequences inside the application process. “We deal with name changes constantly, and they cause a lot of problems,” he says. “Some nationalities keep the wife’s original surname. In systems that expect a married couple to share one, those clients are pushed into a change they never wanted to make.”
Naming laws can also dictate what a name may be. Indonesian passports require at least two name elements, which is why mononym holders often end up duplicating their single name to obtain one.
People who use a single name meet the sharpest version of this everywhere: Many systems demand a given name and a surname, so a mononym holder can be forced to split, duplicate, or invent a name to fit, and United States immigration records routinely enter “FNU,” for “first name unknown,” in the given-name field. Find out how a new country will record your name before you rely on the document, and keep the spelling consistent across everything else you hold.
7. Citizenship can tax you for life no matter where you live
Most countries tax you based on where you live. The United States taxes its citizens on their worldwide income wherever they reside, one of only two countries, with Eritrea, that ties the core income tax to citizenship itself.
An American who has never lived in the country as an adult still owes annual US filings, and the Foreign Account Tax Compliance Act pushes foreign banks to report accounts held by US persons, which is how many so-called accidental Americans learn they owe anything at all.
For Hawker, the model is a reason to stay out. “I would not take on a citizenship that taxes you globally just for holding it,” he says. “I do not see why you should pay a country’s tax simply for being its citizen, and I would not get involved with one that works that way.”
The model is spreading in ambition if not yet in law. In late 2025 a French parliamentary committee adopted an amendment for a targeted tax on wealthy French nationals who move to low-tax countries, treating their income as if they had stayed. Deputies rejected it by a single vote in late October 2025, and France went on to adopt its 2026 budget without it.
Even had it passed, it would not apply where France holds a tax treaty. Advisers now track the direction closely enough. Check whether a citizenship carries a filing obligation that follows you across borders, because shedding it later is expensive.
8. Leaving can cost you an exit tax
Giving up a citizenship or a long-term residence can trigger a tax on the way out, calculated as if you sold everything you own.
The United States taxes covered expatriates on their worldwide unrealized gains at renunciation, as though all assets were sold the day before. You are a covered expatriate if your net worth is $2 million or more, if your average annual net income tax over the prior five years exceeds a threshold ($211,000 for 2026), or if you cannot certify five years of tax compliance. The first $910,000 of gain is excluded for 2026, and the rest is taxed.
Years later, the bill can also land on the people you leave behind. A separate US rule taxes gifts and bequests that a covered expatriate later makes to a US citizen or resident at 40% of their value, above a $19,000 annual exception, and it falls on the American recipient rather than on the person who left. Those regulations took effect in January 2025, with the first return due in July 2027. A clean renunciation today can hand a US grandchild a tax bill decades from now.
Hawker treats an exit tax as disqualifying, and its announcement as a deadline. “If a country has an exit tax, I would not take its citizenship in the first place,” he says. “And if one is coming, I would leave before it arrives.”
Other countries reach departing wealth in their own ways. Canada applies a departure tax, treating most property as sold at fair market value when you cease to be a resident for tax purposes, a trigger that turns on tax residence rather than citizenship or immigration status, so the bill can arrive when you emigrate rather than when you actually sell.
The Netherlands has run a protective exit charge, the conserverende aanslag, since the 1990s, capturing unrealized gains on a shareholding of 5% or more when you emigrate, with interest-free deferral for moves inside the European Economic Area. Price the exit before you plan the entry, because the cost of leaving can dwarf the cost of arriving.
9. Death taxes follow citizenship and domicile, not just your address
Where your heirs get taxed can depend on your citizenship or your long-held ties, not simply where you were living when you died.
The United States taxes the worldwide estate of its citizens regardless of residence, with an exemption of $15 million per person for 2026 and a top rate of 40%. A non-citizen who is not US-domiciled gets far less room, with only $60,000 of US-situated assets, such as US shares or American real estate, exempt before graduated rates rising to 40% apply. Someone holding a US brokerage account or an apartment in Miami can leave heirs a large and unexpected bill.
Hawker draws the line at the rate rather than the principle. “You pay tax your whole life, and then they want it again when you die,” he says. “A reasonable amount is arguable. A heavy one is harder to accept, when that money should be going to your family.”
Connecting factors also change. The United Kingdom replaced domicile with long-term residence for inheritance tax on April 6, 2025; your worldwide estate falls within UK inheritance tax once you have been UK resident for ten of the previous 20 years, and a tail of three to ten years keeps you exposed after you leave. Non-doms who had assumed their foreign assets sat outside the UK net found the basis of the entire system had shifted under them.
Even reliably low-tax jurisdictions test the idea: Swiss voters rejected a proposed 50% federal tax on estates above CHF 50 million in November 2025, keeping succession rules at the cantonal level. Map the estate-tax exposure of every passport and residence you hold, because heirs inherit the tax rules along with the assets.
10. Citizenship can quietly lapse while you live abroad
A citizenship you never formally surrender can still slip away if you live abroad and never build a connection to the country.
Denmark is the clearest live example. Under Section 8 of its Nationality Act, a Dane born abroad who has never lived in Denmark, or spent time there under circumstances showing a real tie, automatically loses Danish citizenship at 22, unless that would leave them stateless. You keep it automatically by living in Denmark for three consecutive months, spending a year there in total before 22, or living seven years in another Nordic country; short of that, retention takes an application filed between the ages of 20 and 22. Miss the window and the citizenship is gone.
Other countries have used the same mechanism. Canada’s former retention rule stripped some second-generation citizens who did not reapply by a set age, a group Bill C-3 has now moved to restore, and South Korea’s inherited citizenship once expired automatically at 22 before the rules tightened.
The principle underneath is the idea of a genuine link: A state can condition citizenship on a real connection, and courts have accepted that long absence with no ties can justify loss. If you hold a citizenship you rarely use, learn whether it carries a retention step, and note the deadline.
11. A citizenship you paid for can be taken back
Purchased citizenship is a legal status like any other, and it can be revoked or invalidated after the fact. In the European Union it now sits under direct scrutiny. In Commission v Malta, the Court of Justice ruled on April 29, 2025, that Malta’s investor-citizenship program breached EU law, holding that the acquisition of Union citizenship cannot result from a commercial transaction.
Malta repealed it three months later through Act No. XXI of 2025, ending the bloc’s last passport-for-investment program. The ruling put every member state on notice against selling nationality.
Cyprus shows the individual version. Since closing its own investor program, its Council of Ministers has moved to strip citizenship from several hundred people naturalized under it, investors and their family members alike, using the revocation power in Article 113 of Law 141(I)/2002.
The same reasoning reaches past investor programs. Italy’s Constitutional Court cited the Malta judgment when it upheld the country’s descent reform, and Italy’s own state lawyers argued that the old bloodline regime would itself have run against EU law for granting citizenship with no real connection to the country. One ruling closed a paid route into the EU in Malta and reinforced a restriction on inherited claims in Rome.
Hawker treats this as an argument for staying informed after the grant, not just before it. “Once you hold the citizenship, keep following the law in that country,” he says. “Rules that let a status be revoked or lapse do change, and you want to hear about it before it reaches you.”
If you hold, or are weighing, a citizenship you acquired rather than inherited, treat its permanence as conditional, and read how the granting country, and the wider legal order it sits inside, can unwind it.
The Through Line
The pattern behind all of them is the same. Acquisition is a moment; citizenship is a status that keeps generating obligations, and the ones that hurt are triggered by law, by time, or by the arrival of a child, long after anyone read the fine print.
Elena Ruda, co-founder and managing partner at Immigrant Invest, reduces the pre-decision test to three questions. “Whether the citizenship passes to children and grandchildren, whether the country carries a military service obligation that could reach a son, and whether the client has political ambitions of their own,” she says. “The first two decide what the status is worth to a family over time. The third can be a reason not to proceed at all, because a number of countries bar dual nationals from elected office and senior public service.”
Eric G. Major, CEO and chairman of Latitude, makes the same argument from the advisory side. “Acquiring a second citizenship is not simply a transaction or an additional travel document,” he says. “It establishes a lifelong legal relationship with a sovereign state, bringing with it rights, obligations and, in some cases, responsibilities that may extend to future generations. These considerations deserve the same level of planning and professional advice as any significant investment or estate planning decision.”
Major argues the point holds for dormant entitlements as much as new applications. “Before claiming a passport, or allowing an existing entitlement to sit dormant, you should understand the legal, tax and succession implications that come with it,” he says. “At Latitude, we have always believed that the best mobility decisions are informed decisions.
A well-structured citizenship strategy is about far more than visa-free travel; it is about ensuring that today’s decisions continue to serve a family’s interests for decades to come, without creating unintended consequences along the way.”
Before you claim a passport, or leave one dormant, find out what deadline it sets, what tax it attaches, whether the granting state can revoke it, and what it hands your children. Every answer is knowable in advance. It only turns expensive when you find it afterward.
