Basic Knowledge of Koseki and Juminyo

There are two citizen documentation systems in Japan: koseki family registry records and juminhyo residential records. Both types of records are strictly confidential. The only people who can get access to those records are the person himself or herself, the direct blood kin, and their attorneys, accountants, and other professional license holders.

To obtain koseki family registry records, you need to provide honseki (permanent domicile) information to the city hall of your jurisdiction. If you don’t know the honseki, you can verify it via juminhyo records.

But the problem is that old juminhyo records are kept for only five years at the city hall. Therefore, if the last known address is more than five years old, it is impossible to obtain the old juminhyo records.

Koseki and Juminhyo


A koseki (戸籍) is a Japanese family registry.
It records births, acknowledgments of paternity, adoptions, disruptions of adoptions, deaths, marriages, and divorces of all Japanese citizens. All Japanese citizens are required to set their honseki (本籍 permanent domicile) in Japan and report all family events to the local city halls where they have set their honseki.

Koseki (Wikipedia)


A juminhyo (住民票) is a registry of current residential addresses. All citizens are required to report his or her current address to the local city hall. A juminhyo records honseki information for Japanese nationals.

Juminhyo (Wikipedia)

Quick Reference for Koseki and Juminhyo

How we work with the records vary depending on the information the client has. Bellow is the quick chart for Japanese registry records.

Honseki No honseki
Previous address

No previous address (N/A)

5 yrs old or older Within 5 yrs
Obtain koseki Assume previous address as honseki and obtain koseki *1 Obtain juminhyo
Current address Current address if honseki matches the previous address Current address

In the case where the previous address was owned by the subject’s family. Usually, we don’t set honseki to the house for rent.

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