Registering a birth abroad: the 3-month deadline, keeping Japanese nationality, and translating the birth certificate

Sources checked: 26 October 2026

When a Japanese child is born outside Japan, the birth must be registered within three months. The foreign birth certificate needs a Japanese translation. If the child also acquired another nationality at birth, you must declare that the child retains Japanese nationality (国籍留保) within the same deadline.

Deadline: three months from the birth

出生の届出は、十四日以内（国外で出生があつたときは、三箇月以内）にこれをしなければならない。

Family Register Act, Art. 49(1): a birth must be registered within 14 days, or within three months if the child was born abroad

The day of birth counts as the first day (Chuo City's guidance: 「生まれた日を含めて3か月以内」).

When you must declare to retain Japanese nationality

If the child also acquired a foreign nationality at birth (for example, by being born in a country that grants citizenship by birthplace), you must declare, together with the birth registration, that the child retains Japanese nationality. Otherwise the child loses Japanese nationality retroactively from birth (Nationality Act, Art. 12; Family Register Act, Art. 104). The declaration is made by writing it in the 「その他」 (other) field of the birth registration form.

If you couldn't file in time for reasons outside your control, such as a natural disaster, the deadline becomes 14 days from when filing became possible (Family Register Act, Art. 104(3)).

A child who lost Japanese nationality this way can reacquire it by notifying the Minister of Justice, if they are under 18 and live in Japan (Nationality Act, Art. 17(1)).

Where to file

The Japanese embassy or consulate in the country of birth (Family Register Act, Art. 40)
The city office of the family's registered domicile (本籍地) in Japan
The city office where the person filing lives (Family Register Act, Art. 25)

Translating the birth certificate

届書に添付する書類その他市町村長に提出する書類で外国語によつて作成されたものについては、翻訳者を明らかにした訳文を添付しなければならない。

Family Register Act Enforcement Regulations, Art. 63 (documents in a foreign language must be accompanied by a translation that identifies the translator)

Chuo City says anyone may translate, including the parent, but the translator must sign at the end of the translation (example wording: 「上記は原文の正訳に相違ありません。訳者の住所・氏名」). Formats can differ between offices, so check the embassy, consulate or city office's own guidance.

Questions

Both parents are Japanese. Do we need to declare retention of nationality?

Not if the child didn't acquire another nationality under the law of the country of birth. The three-month deadline for the birth registration still applies. A child born in a country that grants citizenship by birthplace has acquired that nationality, so the declaration is needed.

We might miss the deadline.

A child who needs the retention declaration loses Japanese nationality if it isn't filed in time. If the deadline is close, contact the office you will file with first.

Can I translate the birth certificate myself?

The Ministry of Justice Q&A and Chuo City's guidance both allow the applicant to translate. Some offices ask for the translator's signature at the end of the translation.

This page is general information. The documents required and the format of translations differ by country and office, and can change. Check the current guidance of the office you are submitting to before you file.