Citizenship Through Parent (Jure Sanguinis)

Japan grants citizenship to children born to at least one Japanese parent, regardless of where the child is born. This is jus sanguinis ("right of blood"), codified in the Japanese Nationality Act and one of the most straightforward pathways to Japanese citizenship. You acquire it automatically at birth if you have a Japanese parent — no residency, financial requirements, or integration tests apply. However, if you were born outside Japan, your parents must notify a Japanese embassy or consulate within three months of your birth, or you lose Japanese nationality retroactively. This is an absolute deadline with no extensions except in cases of force majeure.

The pathway also covers children born out of wedlock to Japanese fathers, who can acquire citizenship by notification if the father has legally acknowledged paternity and the child is under 18.

Japan's Prohibition on Dual Citizenship

Japan does not permit dual citizenship. Under Article 11 of the Nationality Act, you automatically lose Japanese nationality if you voluntarily acquire a foreign nationality.

The Three-Month Deadline for Births Abroad

This is the most critical deadline in Japanese citizenship-by-descent law. If you were born abroad to a Japanese parent and acquire both Japanese and foreign nationality at birth, you will lose Japanese nationality retroactively to the time of birth unless your parents file a notification of intention to retain Japanese nationality within three months of your birth. This deadline has no exceptions except in cases of force majeure.

Nationality Choice for Dual Nationals

If you acquire multiple nationalities at birth and your parents retain Japanese nationality, you must choose one nationality by age 20 (if you became a dual national before age 18) or within two years of becoming a dual national (if you became one at age 18 or older). If you fail to choose, you may lose Japanese nationality.

April 1, 2022 — Age Limit Reduced for Out-of-Wedlock Children

The age limit for acquiring Japanese citizenship through notification as a child born out of wedlock to a Japanese father was reduced from 20 to 18 on April 1, 2022. This change took effect on April 1, 2022. If you were born out of wedlock to a Japanese father, you must file the notification before turning 18, or you lose the opportunity permanently.

January 1, 2009 — Expansion of Rights for Out-of-Wedlock Children

The Nationality Act was amended to allow children born out of wedlock to Japanese fathers to acquire Japanese nationality through notification, even if the parents were not married, provided the father acknowledged paternity. This amendment significantly expanded eligibility and removed the requirement that parents be married.

April 1, 2026 — Changes to Naturalization (Not Citizenship by Descent)

Japan implemented changes to naturalization requirements on April 1, 2026, increasing the residency requirement from 5 years to "10 years or more, in principle." These changes do not apply to citizenship-by-descent, which operates under different legal provisions and remains unchanged.

• Japanese passport — Visa-free or visa-on-arrival travel to numerous countries, including the United States, Canada, Australia, New Zealand, and most of Europe
• Right to live, work, and study in Japan — Without visa restrictions or employment authorization requirements
• Right to own property in Japan — With some limitations on agricultural land
• Right to vote and stand for election — Once you reach voting age (18)
• Access to Japanese social services and healthcare — Including public education, healthcare, and social security benefits
• Right to pass Japanese nationality to your children — If you have children with a non-Japanese partner, your children can acquire Japanese citizenship
• Family register entry (koseki) — Upon acquisition, you are added to the family register of your Japanese parent; this document is essential for all legal transactions in Japan and serves as proof of Japanese nationality
• No visa sponsorship required for employment — You can work in any field without employer sponsorship