When a Japanese citizen and a foreigner get married, what happens to their citizenship?
When a Japanese and a foreigner marry, the marriage may result in the acquisition of citizenship, depending on which country the foreign spouse is from.
There are also cases where a child born to both parents automatically acquires dual citizenship.
This article is about how the marriage of a Japanese citizen to a foreigner affects citizenship.
In Japan, marriage is legally registered through the family register (koseki) system, but this registration alone has no effect on nationality. Citizenship is governed separately under the Nationality Act.
Citizenship of the foreign spouse married to a Japanese
When a Japanese and a foreigner marry, the citizenship of the foreign spouse does not change.
Under the Japanese legal system, citizenship is not conferred by marriage. Therefore, if you marry a Japanese citizen, you do not automatically receive Japanese citizenship.
Even if you are married to a Japanese, you must go through the naturalization process if you wish to obtain Japanese citizenship.
Although marriage itself does not grant nationality, being married to a Japanese citizen can make the naturalization process somewhat easier, such as by reducing the minimum period of residence required before applying.
Citizenship of a Japanese woman married to a foreigner
When a foreign man and a Japanese woman get married, in some cases the Japanese spouse may automatically receive citizenship.
This is because the legal system of some countries provides that a woman who marries a man from that country and becomes his wife receives her husband’s citizenship.
When a Japanese woman acquires the citizenship of her spouse by marriage, she has both Japanese and foreign citizenship and is in a state of dual citizenship.
However, dual citizenship is not allowed in Japan. Within two years of marriage (or when you turn 22), you must choose between Japanese and foreign citizenship.
If you still have not chosen citizenship after this period, you will receive a notification. If you continue to neglect this, you may lose your Japanese citizenship.
A foreign partner who marries a Japanese woman does not acquire Japanese citizenship through marriage, so he remains a foreigner.
In practice, most Japanese women who acquire their husband’s nationality through marriage later renounce that foreign nationality in order to retain their Japanese citizenship, since failure to choose may lead to complications with residency or legal status.
Citizenship of a Japanese man married to a foreigner
When a foreign woman and a Japanese man marry, it usually does not affect the man’s citizenship.
If a Japanese man wishes to acquire the citizenship of his foreign wife, a separate citizenship acquisition procedure is required, based on the laws and regulations of the wife’s country.
A foreign wife who marries a Japanese man does not acquire Japanese citizenship through the marriage, so she remains a foreigner.
In both cases—Japanese man marrying a foreign woman or Japanese woman marrying a foreign man—the foreign spouse must apply for a “Spouse or Child of Japanese National” residence status in order to live legally in Japan.
Citizenship of a child born of a marriage to a foreigner
When a Japanese and a foreigner marry and have a child, there are two types of rules regarding the citizenship the child receives.
- The principle of jus sanguinis ('right of blood’): A child who is born acquires the parent’s nationality.
- The principle of jus soli ('right of the soil’): A child acquires the nationality of the country in which he or she is born, regardless of the nationality of the parents.
For Japan, citizenship is based on the principle of jus sanguinis. If the father or mother is Japanese, the child acquires Japanese citizenship.
If a child is born in a country where citizenship is based on the principle of place of birth, the child acquires citizenship of the country of birth even if the parents do not hold citizenship of that country.
A natural child can automatically receive both citizenships, but Japan does not allow dual citizenship.
Children who have dual citizenship from birth are required by law to choose one citizenship by the age of 22.
Until the age of 22, children with dual citizenship are legally treated as Japanese in Japan, but when traveling abroad they may also use their other nationality’s passport, which can sometimes cause practical issues at border control.
