Densho’s Family History Program provides support to Japanese Americans exploring their heritage. In addition to our educational content, we offer assistance to families wanting to request their koseki (family registers) from Japan. Koseki are the most important genealogical documents for tracing your ancestry in Japan, however, strict privacy laws and language barriers can make requests for koseki challenging. Densho can now assist with these requests, as well as offer translation services that enable families to have a richer understanding of their Japanese ancestry.

What is Koseki?

Modern koseki date back to the early 1870s and are the legal family registers for Japanese citizens. Rather than keeping separate documents for vital records, the Japanese government combines them into one register that includes all the births, adoptions, marriages, divorces, and deaths in one household. One family can have multiple versions of koseki reflecting changes in the head of household or adjustments to the law.

Each local government agency in Japan holds the historical and current koseki for their region. Privacy laws limit access to the koseki and only legally certified, direct descendants of a member of the household may request copies.

Learn more about koseki and how to request them here.

How Densho Can Help

Families can work directly with the local government agencies in Japan to request their koseki. However, there are a number of factors that can make the process challenging or intimidating, namely language barriers and international payment and postage requirements. The language barrier comes up again once families receive their koseki as the documents are written entirely in Japanese.

Densho offers the following services to assist families in this process:

    • Research assistance to find the honseki (registered address in Japan) and family surname kanji. The local government agencies require both of these to request the koseki.

    • Assistance with retrieval of the koseki. This includes corresponding with the local government agency and assisting with international payment and postage.

    • Translation and interpretation of all or some of the koseki.

If you are interested in exploring Densho’s Koseki Retrieval and Translation services please review this page. If you are still interested, you can fill out this form and we will schedule a 30-minute, complimentary consultation to discuss next steps.


Q: Who is eligible for koseki retrieval?
A: Anyone with Japanese ancestry can use Densho’s Koseki Retrieval and Translation services.

Q: What will be required of me?
A: We will need you to provide the paperwork and certificates in order to prove lineage. As the Densho team works to retrieve your koseki, more input could be required from you depending on the requirements of each individual municipality.

Q: Will all koseki retrieval requests be successful?
A: No. There are many reasons why a retrieval may be unsuccessful. Some of the most common are when families cannot find the honseki and/or surname kanji. There is also the possibility that the local government agency cannot locate the koseki or is not willing to release the documents.

Q: How much does it cost?
See the fee structure here.

Q: How long does it take to get your koseki from Japan?
A: It can take anywhere from a few weeks to a few months depending on a number of factors. If you already have the honseki and kanji we can start the retrieval process immediately. The more research needed, the longer it will take. And each local government agency functions differently and the time it takes to request and receive koseki from them varies.

Q: How long do the translations take?
A: Translating each koseki page takes about 30 minutes. The number of pages varies by family.

Koseki Retrieval and Translation Inquiry Form

Please complete this form to inquire about Densho's Koseki Retrieval and Translation services. We will be in touch to set up a 30-minute, complimentary consultation.

Densho Koseki Services and Fees

Densho offers a comprehensive range of services for families who want to research their genealogical roots back to Japan.

In Search of Your Koseki Handout

The koseki, or family register, is a record of the Japanese population by household. Learn more about koseki, how to obtain it, and other information.