Japanese naturalization (帰化): requirements and step-by-step process

The Japanese naturalization process (帰化, kika) runs through the Legal Affairs Bureau (法務局, hōmukyoku) for your address, not the immigration office. You book a consultation, collect documents, apply in person, go through review, and the Minister of Justice decides. Approval is published in the Official Gazette (官報). The law requires 5 years in Japan, but since April 1, 2026 the Ministry of Justice expects 10 years in principle. There is no fee. This is the position as of October 2026.

What are the requirements for Japanese naturalization?

Article 5 of the Nationality Act (国籍法) sets six conditions. The Ministry of Justice says they are minimums: meeting them does not guarantee approval.

The Ministry also requires Japanese good enough for daily life, in speaking, reading and writing, and integration into Japanese society.

What changed on April 1, 2026?

The Minister of Justice announced on March 27, 2026 that, from April 1, naturalization review requires in principle 10 years of stay as part of “integration into Japanese society”. The checking period for taxes and social insurance also got longer. The Ministry’s leaflet now lists 10+ years of stay as an example of integration.

Kyodo News reported the details from the Ministry: taxes are now checked for 5 years instead of 1, and social insurance for 2 years. Kyodo also reported the new approach applies to people who applied before April 1.

The Nationality Act did not change. The 5-year legal minimum still applies, and 10 years is now the operating standard on top of it.

Who can use a shorter route?

Articles 6 to 8 of the Nationality Act relax some conditions for people with close ties to Japan.

Good conduct, the one-nationality rule and the constitution condition still apply to these routes.

What are the steps?

While your application is pending, tell the bureau promptly if anything changes: a new address, marriage or divorce, a birth, a visa renewal, a trip abroad, a job change, or any violation of the law, including traffic violations.

What documents do you need?

The Ministry’s guide (帰化許可申請のてびき, April 2026 edition) lists, among others:

• application form with photo
• outline of your relatives, CV, and diplomas or school certificates
• statement of motivation (動機書), handwritten
• oath (宣誓書), given to you when you apply
• certificates of Japanese ability or other skills, and a copy of your driving license if you have one
• proof of nationality and family relationships from your home government: nationality certificate, birth certificate, marriage certificates, passport copy
• residence records (住民票) for your household
• employment and salary certificate, bank records, lease
• tax certificates, as directed by the bureau
• health insurance information and 2 years of social insurance payment records
• a driving record certificate for the past 5 years if you drive

Most documents are needed in 2 sets: one original and one copy. Use A4 paper and a black pen, not an erasable pen. Every foreign-language document needs a full Japanese translation with the translator’s name, address and date. The translator can be anyone who translates accurately, including you.

Do you have to give up your nationality?

Yes, in principle. You must be stateless or lose your current nationality when you become Japanese. If your country’s law takes away its nationality automatically on naturalizing (the guide gives Korea as an example), you don’t need a loss certificate. Otherwise the bureau may ask for a certificate from your government showing you have lost, or will lose, that nationality.

The Minister can make an exception only if you cannot give up your nationality by your own will and have special family ties or circumstances in Japan.

How long does it take, and what does it cost?

The Ministry publishes no processing time. One administrative scrivener office that handles naturalization reports about 1 year from application to Gazette publication, depending on your status and the bureau’s workload. Add the time it takes to collect home-country documents before you apply.

Is naturalization right for you?

Once naturalized, you are no longer under residence control by immigration, according to ISA. But you also give up your current citizenship in principle. Many long-term residents compare it with permanent residency (永住) first: see permanent residency vs naturalization and the permanent residency requirements.

More guides: spouse visa in Japan, visa renewal in Japan.