| Passport | Dual nationality | As published | Taxes citizens abroad | Route to citizenship |
|---|
| 🇩🇰 Denmark | Allowed | Yes, since 2015 | No | 9 years of residence, tests required |
| 🇫🇮 Finland | Allowed | Yes | No | 8 years of residence since the 2024 reform |
| 🇫🇷 France | Allowed | Yes | No | 5 years of residence, 2 with a French degree |
| 🇩🇪 Germany | Allowed | Yes, since 2024 | No | 5 years of residence since 2024 |
| 🇮🇪 Ireland | Allowed | Yes | No | 5 years of residence, 1 continuous before applying |
| 🇮🇹 Italy | Allowed | Yes | No | 10 years of residence, 4 for EU nationals |
| 🇳🇴 Norway | Allowed | Yes, since 2020 | No | 8 years of residence in the last 11, 7 for some categories |
| 🇧🇪 Belgium | Allowed | Yes | No | 5 years of legal residence |
| 🇱🇺 Luxembourg | Allowed | Yes | No | 5 years of residence, language test |
| 🇵🇹 Portugal | Allowed | Yes | No | 10 years of residence, 7 for EU and CPLP nationals, since May 2026 |
| 🇸🇪 Sweden | Allowed | Yes | No | 8 years of residence since June 2026, language and civics tests, income floor |
| 🇨🇭 Switzerland | Allowed | Yes | No | 10 years of residence on a C permit, plus 2 to 5 years in the canton depending on the canton |
| 🇬🇷 Greece | Allowed | Yes | No | 7 years of residence, language test |
| 🇳🇿 New Zealand | Allowed | Yes | No | 5 years as a resident |
| 🇬🇧 the United Kingdom | Allowed | Yes | No | 5 years to settlement, 1 more to citizenship. 2025 reform moves settlement toward 10 years for most routes, verify |
| 🇦🇺 Australia | Allowed | Yes | No | 4 years of residence, 1 as a permanent resident |
| 🇨🇿 the Czech Republic | Allowed | Yes, since 2014 | No | 5 years as a permanent resident |
| 🇭🇺 Hungary | Allowed | Yes | No | 8 years of residence |
| 🇲🇹 Malta | Allowed | Yes | No | 5 years in the last 7, discretionary |
| 🇵🇱 Poland | Allowed | Yes | No | 3 years as a permanent resident |
| 🇨🇦 Canada | Allowed | Yes | No | 3 years of residence within 5 as a permanent resident |
| 🇸🇮 Slovenia | Allowed | Yes | No | 10 years of residence, 5 continuous |
| 🇺🇸 the United States | Allowed | Yes | Yes, worldwide, for life | 5 years as a green card holder, 3 if married to a citizen |
| 🇮🇸 Iceland | Allowed | Yes | No | 7 years of residence |
| 🇧🇬 Bulgaria | Allowed | Yes | No | 5 years of permanent residence |
| 🇨🇾 Cyprus | Allowed | Yes | No | 7 years of residence, 5 in some cases |
| 🇷🇴 Romania | Allowed | Yes | No | 8 years of residence |
| 🇦🇷 Argentina | Allowed | Yes | No | 2 years of residence, court process |
| 🇧🇷 Brazil | Allowed | Yes | No | 4 years of residence, 1 if married to a Brazilian |
| 🇲🇽 Mexico | Allowed | Yes | No | 5 years of residence, 2 if married |
| 🇰🇳 St Kitts and Nevis | Allowed | Yes | No | Citizenship by investment, months not years |
| 🇦🇬 Antigua and Barbuda | Allowed | Yes | No | Citizenship by investment, months not years |
| 🇬🇩 Grenada | Allowed | Yes | No | Citizenship by investment, months not years |
| 🇱🇨 St Lucia | Allowed | Yes | No | Citizenship by investment, months not years |
| 🇩🇲 Dominica | Allowed | Yes | No | Citizenship by investment, months not years |
| 🇻🇺 Vanuatu | Allowed | Yes | No | Citizenship by investment, months not years |
| 🇹🇷 Turkey | Allowed | Yes | No | 5 years of residence, or citizenship by investment |
| 🇳🇷 Nauru | Allowed | Yes | No | Citizenship by investment, 3 to 4 months |
| 🇭🇷 Croatia | Allowed, with conditions | Yes, with exceptions | No | 8 years of continuous residence |
| 🇸🇰 Slovakia | Allowed, with conditions | Yes, after 5 years abroad | No | 8 years of residence |
| 🇮🇱 Israel | Allowed, with conditions | Yes under the Law of Return. Naturalization normally requires giving up the other passport | No | Law of Return: Jews, their children, grandchildren, and spouses become citizens on arrival |
| 🇷🇺 Russia | Allowed, with conditions | Yes, must declare | No | 5 years of residence |
| 🇿🇦 South Africa | Allowed, with conditions | Yes, with prior permission | No | 5 years as a permanent resident |
| 🇹🇭 Thailand | Allowed, with conditions | Yes, tolerated | No | 5 years as a permanent resident |
| 🇰🇷 South Korea | Restricted | Restricted, some categories | No | 5 years of residence |
| 🇪🇸 Spain | Restricted | Restricted, Ibero-American nationals excepted | No | 10 years, 2 for Ibero-American nationals |
| 🇦🇹 Austria | Restricted | No, with exceptions | No | 10 years, 6 in some cases |
| 🇳🇱 the Netherlands | Restricted | No, with exceptions for spouses and birth | No | 5 years of residence |
| 🇦🇪 the UAE | Restricted | Case by case | No | No standard path |
| 🇱🇻 Latvia | Restricted | Restricted to EU, EFTA, NATO and a few others | No | 5 years as a permanent resident, language test |
| 🇱🇹 Lithuania | Restricted | No, narrow exceptions | No | 10 years of residence, language test |
| 🇲🇨 Monaco | Restricted | Generally no, verify | No | 10 years of residence, then a sovereign decision |
| 🇺🇦 Ukraine | Restricted | Restricted, reform in progress | No | 5 years of residence |
| 🇹🇼 Taiwan | Restricted | Restricted | No | 5 years of residence, renunciation usually required |
| 🇸🇦 Saudi Arabia | Restricted | No, exceptions by decree | No | 10 years, discretionary, Premium Residency is the realistic prize |
| 🇸🇬 Singapore | Not allowed | No | No | PR first (2 to 6 years), citizenship 2 years after PR, discretionary |
| 🇯🇵 Japan | Not allowed | No | No | 5 years of residence, 3 as a work permit holder |
| 🇪🇪 Estonia | Not allowed | No | No | 8 years, 5 as a permanent resident |
| 🇲🇾 Malaysia | Not allowed | No | No | 10 years of residence, rarely granted |
| 🇱🇮 Liechtenstein | Not allowed | No | No | 30 years, or 10 with a community vote |
| 🇦🇩 Andorra | Not allowed | No | No | 20 years of residence, 10 for some |
| 🇭🇰 Hong Kong | Not allowed | Chinese nationality law, no dual | No | 7 years of residence for permanent residency, nationality is Chinese |
| 🇶🇦 Qatar | Not allowed | No | No | 25 years of residence, rarely granted |
| 🇨🇳 China | Not allowed | No | No | Almost never granted to foreigners |
| 🇮🇩 Indonesia | Not allowed | No | No | 5 years of residence, renunciation required |
| 🇮🇳 India | Not allowed | No, OCI card instead | No | 12 years of residence, renunciation required |
