How many citizenships you can hold

There is no international limit on how many nationalities a person may hold. The constraints are national and they differ sharply.

The three positions

• Permissive. No limit and no objection: the United Kingdom, Ireland, Canada, Australia, most of Latin America, and — since its 2024 reform — Germany.
• Conditional. Permitted with exceptions, or permitted for those acquiring by birth or descent but not by naturalisation. Spain's arrangement with specified countries is the well-known example.
• Prohibited. Acquiring another ends the first, or naturalising requires renouncing: Austria, Japan, China, Singapore, India and others.

Positions change. Several countries have liberalised in the last decade and a few have tightened, so this is checked at the date rather than remembered.

The practical problems of holding several

• Which passport at which border. Countries that require their citizens to use their own document create a sequencing problem on a multi-leg trip.
• Expiry management. Several documents on several calendars, renewed at different consulates with different processing times.
• Compliance friction. Every additional nationality is a field on every bank form and an additional screening pass.
• Obligations multiply. Military service, filing duties and notification requirements attach per nationality, not per person.
• Consular protection weakens. A state generally cannot protect you against another state whose citizen you also are — the situation where protection is most needed.

The sensible number

For most people, two: one that is home and one that solves a specific problem — mobility, a base, a fallback. A third earns its place only where it does something the other two cannot, and each one added has a maintenance cost that is paid in administration for the rest of your life.