氏名・名字
Japanese names generally combine a family name with a given name, with the family name first in Japanese writing. The legal term for the surname is uji, written 氏; everyday terms include myōji and sei. Written characters, pronunciation and a family’s legal surname are related but distinct matters with changing rules.
A written name and its pronunciation are separate records.
Japanese name order and differing Roman-letter conventions need separate explanation.
The addition of readings to family registers from 2025 did not require everyone to choose a new name.
Shimei combines a family surname and a personal given name. In the government example YAMADA Haruo, YAMADA is the family name and Haruo the given name. Capitalizing the surname helps readers identify the two parts.
An official passport-form example from Japan’s consulate in Los Angeles uses 外務 太郎. Its katakana fields give ガイム タロウ, and the surname and given-name fields in Hepburn romanization give GAIMU and TARO. Kanji, a katakana reading and romanization represent the same example in different ways. This is an official filling example, not a reading guessed from kanji or a private applicant’s record.
| Form | Family name | Given name |
|---|---|---|
| Kanji | 外務 | 太郎 |
| Katakana | ガイム | タロウ |
| Hepburn romanization | GAIMU | TARO |
A child’s given name can use the specified jōyō and jinmeiyō kanji, as well as hiragana or katakana. Both the Justice Ministry’s character-database explanation and Handa City’s 2026 birth-registration guidance include kana. Permission to use a character does not by itself determine a name’s reading. Marital family-name choice, given-name characters and registered pronunciation concern different rules.
Specified kanji, hiragana or katakana.
Confirmed and recorded separately; character eligibility does not determine its pronunciation in a name.
Written kanji and actual pronunciation need separate confirmation; the register records readings in katakana. The Justice Ministry describes a general requirement for readings normally recognized for the name’s written characters, rather than one compulsory dictionary pronunciation for each character. People already registered who actually use another reading have a separate evidentiary route, with passports or bankbooks among the examples of established use. That situation differs from a newborn’s first registration.
For an already registered person using another reading, a separate route allows evidence of established use.
Birth and other first entries include a reading with the registration; the established-use route is a different situation.
A 2019 government agreement sets family-name-first order for Japanese names in official documents, using full capitals for the surname where needed, as in YAMADA Haruo. Implemented from 2020, it retains exceptions for matters such as prescribed international formats and systems. Private writing and different publications need to be understood in their own contexts.
Nara’s Man’yō Culture Museum records the historical name 藤原朝臣不比等, with the reading ふぢはらのあそみふひと. Read alongside its explanation of the eight kabane ranks, the name distinguishes the Fujiwara clan, the kabane Asomi and the personal name Fuhito. The eight-rank arrangement of 684 ordered clan status. Here kabane is not a modern family surname, a Western-style middle name or a ministerial office.
The museum records the full reading as ふぢはらのあそみふひと.
Tateyama City’s history explains that Yoshishige, of Minamoto lineage, developed and settled the Nitta estate and took the name Nitta. His brother Yoshiyasu inherited the Ashikaga estate and used Ashikaga. Different house names could thus exist within a shared clan genealogy. This medieval warrior example links naming to a landed base without making every modern Japanese surname a place-name derivative.
Two specific examples within Minamoto lineage
Develops and settles the Nitta estate → uses Nitta as the house name.
Inherits the Ashikaga estate → uses Ashikaga as the house name.
These examples link house names to landed bases; they do not establish a universal surname origin.
The National Archives explains that people outside the warrior class could also have family names in the Edo period, while their public use was restricted. Permission for commoners to use surnames publicly in 1870 therefore does not mean that every commoner acquired a family name for the first time that year.
Some people outside the warrior class also had family names.
Public use was restricted; possession and public use differed.
The government permitted commoners’ public surname use in 1870 and made surname use obligatory in 1875. Those uncertain of an ancestral name were to establish one. Existing names and newly chosen names could therefore both enter the system. Permission and compulsion were separate policy changes.
The Justice Ministry’s history describes an 1876 instruction for wives to retain their birth surname, alongside a social custom of using the husband’s. Under the Meiji Civil Code from 1898, family members used the household’s surname. An instruction, a social practice and the later household system should not be collapsed into one unchanged rule.
The former Civil Code linked a couple’s shared surname to membership in the same ie, or legal house. The 1947 family-law revision abolished the house and household head, while a couple agreed at marriage to use either spouse’s surname. The shared-surname principle continued, but its institutional basis and means of choice changed. The Justice Ministry also explains debate over optional separate surnames; situations such as international marriage have additional conditions.
The spouses agree to use either spouse’s surname
Membership of the same legal house → the house’s shared surname.
House and household head abolished → agreement to use either spouse’s surname; shared-surname principle retained.
The koseki registers and certifies civil-status and family relationships for Japanese nationals, including births, marriages and deaths; it is not a list organized by present residential address. Kagoshima City describes its basic unit as a couple and their unmarried children sharing the surname, managed at the registered domicile. This is an organizing principle, not a claim that every existing register has exactly that set of living members.
An illustrative family group
Organizing principle: a couple and their unmarried children sharing the surname. This is neither a present-address list nor a statement of every register’s actual membership.
The people form an example only. The book is a conceptual record carrier, not an official register design.
The system introduced on May 26, 2025 adds katakana name readings to the koseki. For people already registered, the municipality of registered domicile consulted administrative reading information, including that kept for residence-record work, and notified people of the proposed reading. A pronunciation held elsewhere for administrative convenience was not already a certified reading in the koseki; the written name and its newly recorded reading are related records.
Written name. A reading kept elsewhere for administrative convenience was not already certified in the koseki.
Katakana name reading; no requirement for everyone to choose a new name.
During the reporting period, a correct notified reading required no report; an incorrect one required a corrected report, with the accepted reading entered. Without a report, the municipal head records the notified reading after obtaining the relevant legal-affairs authority’s permission. First entries following birth or naturalization take a different route: the reading accompanies that initial registration.
The illustrations distinguish carriers and stages. The branches below determine whether a report is needed and how the reading is entered.
Two paths after notification for people already registered, during the reporting period that has ended
An incorrect notified reading is corrected by a report → the accepted reading is entered.
A correct notified reading requires no report. Without a report → the municipal head obtains the relevant legal-affairs permission → the notified reading is entered.
Birth, naturalization and other first entries: report the reading with that registration.
The one-year reporting period ended on May 25, 2026. Municipal recording of notified readings applies from May 26 onward, rather than proving that every register was completed that day. A reading recorded through this no-report route has a one-time change provision without family-court permission; a later change after one’s own report is treated differently. The date alone does not establish an individual record’s status.
A one-time change provision does not require family-court permission.
A different situation; the preceding route must not be applied to it.
YAMADA is the family name; Haruo is the given name. The example puts the family name first.
The first permitted commoners’ public surname use; the second made surname use compulsory. Some commoners had family names before either change.
No. Justice Ministry guidance also includes hiragana and katakana. Permitted characters and the reading are separate questions.
No. It added a record of pronunciation alongside the written name.
外務 太郎 is given as ガイム タロウ, with GAIMU and TARO in the surname and given-name fields; the reading is supplied, not guessed.
No. It is a kabane rank, distinct from the Fujiwara clan name and the personal name Fuhito.
No. It dates the applicable route for notified readings without reports, not completion of every individual record.
The name table re-typesets an official filling example. Relationship diagrams, timelines and HO illustrations of people and record carriers explain the cited material. They are not official documents or portraits of named individuals.