Marriage Between Two Foreigners in Japan
Marriage between two foreigners in Japan follows a track distinct from marriage to a Japanese national: both partners must independently prove their own eligibility to marry, and the marriage itself never creates a koseki (family register) entry for either person.1 Choosing the wrong registration path, or assuming the process mirrors a Japanese-foreign marriage, can add weeks to the affidavit timeline or complicate a later spouse-visa filing.
Procedures, fees, and requirements can change. Confirm current details at the Ministry of Justice (法務省) family register guidance and the Immigration Services Agency (出入国在留管理庁, ISA). This article is general information, not legal, tax, or immigration advice; for your specific case, consult a licensed immigration lawyer (弁護士) or gyoseishoshi (行政書士, administrative scrivener), particularly if you have cross-border assets, a planned property purchase, inheritance or succession concerns, or a complex visa-eligibility question.
Overview
A marriage where both parties are foreign nationals becomes legally valid for purposes recognized in Japan either by filing a 婚姻届 (konin todoke, marriage registration form) at a Japanese municipal office under Japan's registration system, or by marrying under a method valid in one partner's home country and, where relevant, reporting that marriage to a Japanese municipal office afterward.1
Because neither partner is a Japanese national, the requirements for the marriage to be valid, such as age, capacity, and the absence of an existing marriage, are governed separately for each partner by that partner's own national law. Each partner must independently demonstrate their own eligibility, rather than one relying on the other's home-country law.2
This is the key structural difference from Marriage to a Japanese National. There, the Japanese partner's eligibility is verified through the koseki system, and only the foreign partner needs a certificate of legal capacity to marry. Marriage to a Japanese National covers that asymmetric case in full; here, because both partners are foreign, both need their own certificate.1
The terms below recur throughout this article:
| Japanese term | Romaji | English gloss |
|---|---|---|
| 婚姻届 | konin todoke | Marriage registration form |
| 婚姻要件具備証明書 | konin yōken gubi shōmeisho | Certificate of legal capacity to marry (affidavit of competency to marry) |
| 戸籍 | koseki | Family register |
| 受理証明書 | juri shōmeisho | Acceptance certificate (proof a notification was accepted) |
The Two Registration Paths
Two structural paths exist for a foreign-foreign couple whose marriage needs to be recognized in Japan.
- Path A, Japan-side: both partners jointly file a konin todoke at a Japanese municipal office, each providing their own affidavit of competency and passport. The marriage becomes valid, for purposes recognized in Japan, the moment the office accepts the notification.13
- Path B, home-country-first: the couple marries first under a method valid in one partner's home country (civil registry, a religious system recognized by that country's law, or that country's embassy or consulate procedure). If they later need the marriage reflected on the Japanese side, for a future status-of-residence application, for example, they report it at a Japanese municipal office with the foreign marriage certificate and a Japanese translation.145
A third practical variant sits inside path B. If a partner marries at their own country's embassy or consulate located in Japan, using that country's marriage method, filing at a Japanese municipal koseki window is not required at all. Municipal practice treats an in-Japan embassy marriage the same as a marriage performed abroad, since both are foreign-method marriages rather than Japan-method ones.6
Which country's law governs the marriage's substantive validity, its ongoing effects such as surname, marital property, and inheritance can differ depending on where and how the couple marries and on each partner's nationality and habitual residence. This carries downstream implications distinct from the simple procedural choice of where to file paperwork; see "Which Country's Law Applies to Property and Inheritance" below.2
Register Marriage in Japan
This section covers the Japan-side path in more detail: where to file, what each partner needs to bring, and what the marriage does and does not create in Japan's registration system.
The Konin Todoke (Marriage Registration Form)
Marriage to a Japanese National covers the general konin todoke filing mechanics, including the two-witness requirement and same-day legal effect, in depth. This article does not repeat that detail; it focuses on what changes when both partners are foreign nationals.
The biggest structural difference is where the couple files. For a marriage to a Japanese national, the couple can choose between the Japanese partner's 本籍地 (honsekichi, "registered domicile") or the couple's current address. A foreign-foreign couple has no such choice, because neither partner has a registered domicile in Japan's koseki system.
Family Register Act Article 25(2) requires a notification involving a foreign national to be filed at the locality of the notifying persons' address (所在地), rather than a registered domicile.7 For a foreign-foreign couple specifically, this means filing is anchored to whichever municipality is the address of either partner, and a licensed gyoseishoshi firm's practical guide confirms the same rule in plain terms.76
| Requirement | Detail | Source |
|---|---|---|
| Filing location | Municipal office covering the couple's address (所在地); no registered-domicile option | 7 |
| Filing fee | None | 3 |
| Witnesses | Two adults (18 or older), any nationality | 89 |
| Seal (hanko) | Optional since 2021-09-01; a signature alone is enough | 10 |
| Each partner provides | Own affidavit of competency to marry, plus passport | 13 |
If a municipal office declines to accept the konin todoke, the filer may appeal to family court, the same recourse available in a Japanese-foreign marriage.3
Not every ward's public marriage-guidance page addresses the foreign-foreign scenario explicitly. Chuo City, Tokyo, has a page written specifically for foreign-national parties to a family register notification.9
Funabashi City's page on marriage to a foreign national or marriage abroad, by contrast, is written for the case where at least one party is Japanese and does not address the foreign-foreign scenario at all. It directs foreign-foreign filers whose partner cannot obtain a certificate of legal capacity to contact the office directly.11 Do not assume a given ward's page covers your situation; confirm directly if both partners are foreign.
Both Partners Need Affidavits of Competency
Each partner must submit their own 婚姻要件具備証明書 (certificate of legal capacity to marry, or affidavit of competency to marry), issued by an authority with authority under that partner's own home-country law, attesting that the marriage meets that country's requirements.1
This is a structural consequence of how Japanese private international law assigns governing law: each party's eligibility to marry is determined under that party's own national law. In a foreign-foreign marriage both partners carry this burden independently; there is no koseki system standing in for one side, as there is for the Japanese partner in a Japanese-foreign marriage.21
Where a partner's country has no system for issuing this certificate, Japanese municipal practice accepts a substitute: a sworn statement made before that country's resident consul in Japan, or a combination of passport, national ID, certificate of nationality, civil-registry extract, or birth certificate, each with a Japanese translation.1
Effective September 1, 2025, the U.S. Embassy and consulates in Japan stopped notarizing affidavits of competency to marry; the Embassy does not issue this certificate at all. It instead publishes a downloadable PDF statement that a U.S. citizen presents to their local ward office, showing that no such U.S. certificate exists. If a ward insists on notarization instead, the Embassy's guidance points to remote online notarization services offered by some U.S. states (as of 2026-07-24; confirm current figures with the U.S. Embassy Tokyo).12
British nationals obtain a marital status affirmation or affidavit from the British Embassy in Tokyo only, not the Osaka consulate. The process runs through an online application (fee £50) followed by an in-person appointment available only Tuesday or Wednesday, booked at least seven days after the online application (as of 2024-05-09).13
Filipino citizens obtain a Legal Capacity to Contract Marriage Certification (LCCM) from the Philippine Embassy in Tokyo, built on a DFA-apostilled, PSA-issued Certificate of No Marriage (CENOMAR, valid six months) and a DFA-apostilled PSA birth certificate (as of 2026-07-24).14
Because both partners need their own affidavit, and issuance timelines differ sharply by nationality, from a same-day PDF statement to a multi-week PSA-apostille chain, the couple's realistic timeline is set by whichever partner's home-country process is slower, not by either process alone.121314
Both partners need their own certificate of legal capacity to marry, and issuance timelines differ sharply by nationality. Plan around whichever partner's home-country process is slower, not whichever is faster; a same-day statement for one nationality does not mean the couple can register that quickly.121314
Fees and processing details for these three nationality examples, current as of the dates shown, illustrate how differently the affidavit process can run for each partner; confirm your own country's requirements directly with your embassy or consulate (as of 2026-07-24).
| Item | Amount | As of | Source |
|---|---|---|---|
| Konin todoke filing (any nationality) | Free | current | 3 |
| UK marital status affirmation/affidavit | £50 | 2024-05-09 | 13 |
| Philippine LCCM | ¥3,750 | 2026-07-24 | 14 |
| Philippine Affidavit of Civil Status | ¥3,750 | 2026-07-24 | 14 |
| Philippine express processing (per document) | +¥1,500 | 2026-07-24 | 14 |
| U.S. affidavit notarization | Discontinued 2025-09-01; no certificate issued, no fee | 2025-09-01 | 12 |
This article covers these three nationality examples rather than a comprehensive country-by-country guide. A planned dedicated article on the affidavit of competency will cover country-specific issuance processes in more depth.
Name Choices When Registering in Japan
Civil Code Article 750 requires a married couple to adopt a single shared surname, but this rule operates through the koseki mechanism. Since neither partner in a foreign-foreign marriage receives a koseki entry, the single-surname requirement does not mechanically apply.81
Instead, which law governs a foreign-foreign couple's surname as a legal matter follows the general private-international-law rule for the effects of marriage: the couple's common national law if they share one, otherwise the law of their common habitual residence, otherwise the law of the place with the closest connection.2
Practically, each partner can keep or change their own name independently for Japanese administrative purposes. A partner's home country may have its own separate expectations about surname change on marriage, which the couple should confirm with their respective embassies.812 A planned dedicated article on choosing surnames in international marriages will cover name-choice mechanics in more depth; this article only flags the difference from Japan's single-surname rule for Japanese couples.
No Koseki Entry Is Created
When a konin todoke is accepted and both parties are foreign nationals, no koseki (family register) entry is created for either party. The Ministry of Justice's own koseki Q&A states this directly: on acceptance, a Japanese national is recorded in a koseki, while for a foreign-foreign marriage the notification documents (届書) are instead preserved as documents, not entered into any koseki.1
That retention period runs 50 years from the year following receipt, under the Family Register Act's Enforcement Regulations; other, non-marriage documents are preserved for 10 years (as of 2026-07-30; confirm current figures with the Ministry of Justice).15
Because no koseki is created, a foreign-foreign couple who later needs to prove the marriage, for a status-of-residence application, for example, relies on the acceptance certificate (受理証明書) from the municipal office, or the original foreign marriage certificate if the marriage was established abroad, not a koseki transcript.9 It is easy to assume, by analogy with a Japanese-foreign marriage, that some koseki-adjacent document will exist. It does not.
This contrasts with a marriage to a Japanese national, where the foreign spouse doesn't receive a koseki entry either, but the Japanese spouse's existing koseki, or a newly created one, is updated to record the marriage. In a foreign-foreign marriage, there is no Japanese-national party whose koseki could be updated, so no koseki record is created for anyone.1
Marrying in One Partner's Home Country First, Then Registering in Japan
This section covers the alternative path: marrying first under one partner's own country's system, then deciding whether the marriage needs to be reported to Japan.
When This Path Makes Sense
A gyoseishoshi firm's guidance on international marriage where a partner is not currently in Japan describes marrying abroad first as a distinct procedural track from marrying in Japan first, without asserting that one is generally more common or simpler. The firm frames the choice around practical circumstances, such as where each partner currently is and whether a certificate of legal capacity is obtainable for both parties, rather than a universal recommendation.5
It is sometimes suggested in expat forums and general guides that most foreign-foreign couples in Japan choose to register in Japan first, for procedural simplicity. That pattern could not be confirmed against any citable primary or professional source; treat it as an anecdotal impression, not a documented fact.
Marrying under one partner's home-country method means that country's law governs the marriage's formal validity, and depending on the applicable-law analysis under Japan's Act on General Rules for Application of Laws, may also be more likely to govern the marriage's ongoing effects, particularly where both partners share the same nationality, since shared national law is the first-tier rule for a marriage's effects.2
If both partners share the same nationality, marrying via that shared home country's system may be simpler in the sense that only one country's substantive marriage law and documentation system is involved, rather than the affidavit-of-competency process running in parallel for two different nationalities. This is a structural inference from the applicable-law framework, not a claim about administrative convenience specifically.2
Reporting to Japan After Foreign Marriage
If a foreign-foreign marriage is established abroad, or at a home-country embassy or consulate located in Japan, filing at a Japanese municipal koseki window is not legally required for the marriage's own validity. Reporting to Japan becomes relevant mainly when the couple needs the marriage reflected on the Japanese side for some other purpose, such as a future status-of-residence application.6
Where a couple does report a marriage established abroad, the required documents generally include the original foreign marriage certificate with Japanese translation, plus each partner's nationality certificate or passport, also translated, with the translator's name recorded. The couple may translate the documents themselves.15
Required documents can vary by municipality; confirm the specific list with the receiving ward office before filing.5
Reporting to Home Countries
Why Home-Country Reporting Matters
Whether and how a partner must separately report their marriage to their own home-country government varies sharply by nationality; there is no uniform rule. The following examples illustrate genuinely different approaches, since each turns on the reporting partner's own nationality, not on the other partner's nationality or status.121316
The U.S. Embassy Tokyo states that marriages legally performed and valid abroad, which includes a Japan-method marriage, are also legally valid in the United States, and that a U.S. citizen does not have to report the marriage to the Embassy or Consulate for it to be recognized. The U.S. government does not issue its own marriage certificate for marriages performed overseas.12
A marriage will be recognized in the UK automatically if the couple followed the correct legal process in the country where they married and the marriage would be allowed under UK law. Gov.uk describes no separate UK registration requirement for this scenario.13
A Filipino national whose marriage was registered in a specified set of Japanese prefectures, including Tokyo, Kanagawa, Chiba, Saitama, and Hokkaido, among others, must report it to the Philippine Embassy in Tokyo as a Report of Marriage (ROM) within one year of the marriage. Filing after that window requires an additional Affidavit of Delayed Registration executed at the embassy. Standard ROM processing takes 10 working days once complete documents are received (as of 2026-07-24; confirm current figures with the Philippine Embassy Tokyo).16
This is a genuine nationality-dependent contrast: home-country reporting is mandatory and time-limited for at least one nationality verified here, unlike the U.S. and UK examples, where no reporting obligation exists.
Good to know
Affidavit Processing Times Vary Significantly by Nationality
Both partners need their own certificate of legal capacity to marry, and the slower of the two nationalities' processes sets the couple's realistic timeline, not the faster one. Processing paths differ sharply by nationality, from a same-day statement with no formal certificate issued, to an in-person embassy appointment with a minimum booking lag, to a multi-step process built on a document with its own validity window before the embassy will even issue the certificate.121314
Budget for the slower partner's process from the start, rather than assuming both certificates will be ready on the same schedule, and confirm current timelines directly with each partner's own embassy or consulate.
Which Country's Law Applies to Property and Inheritance
Marrying in Japan does not automatically mean Japanese law governs every consequence of the marriage. Under the Act on General Rules for Application of Laws, the law governing marital property follows the same hierarchy used for the marriage's general effects: the couple's shared national law, then shared habitual residence, then the place with the closest connection. Spouses may jointly select a different governing law in writing from a limited set of options: a country of either spouse's nationality, either spouse's habitual residence, or, for real property, the property's location.2
Inheritance is governed by a separate rule, the national law of the deceased, not the country where the marriage was registered.2 This is not legal advice. Couples with cross-border assets, a planned property purchase in either country, or existing succession concerns should consult a licensed immigration lawyer (弁護士) or gyoseishoshi (行政書士) before assuming which country's law applies to their situation.
Spousal Visa Eligibility After Registration
Registering a foreign-foreign marriage in Japan does not by itself change either partner's status of residence. Marriage registration and any status-of-residence filing are legally and administratively separate processes, handled by different offices, a municipal koseki window versus a regional immigration bureau.11718
There is no single uniform "spouse" status of residence for a foreign-foreign couple, the way "Spouse or Child of Japanese National" exists for a Japanese-foreign couple. Depending on which status the sponsoring partner already holds, the other partner may become eligible to apply for "Spouse or Child of Permanent Resident," if the sponsoring partner holds permanent residence or is a special permanent resident, or "Dependent," if the sponsoring partner holds one of a defined list of work or study statuses, including Professor, Engineer/Specialist in Humanities/International Services, Intra-company Transferee, and Student, among others. In many other cases, marriage creates no new eligibility at all, and each partner continues on their own independent status.1920
Whichever status may apply, it still requires its own Certificate of Eligibility application, if the applying partner is outside Japan, standard processing 1-3 months, no fee, or a change-of-status application, if already in Japan on another status, standard processing 1-2 months, fee ¥6,000 paper or ¥5,500 online. Neither is automatic or triggered by the marriage registration itself (as of 2026-07-24; confirm current figures with the Immigration Services Agency).1718
A planned dedicated article on the spouse-visa application after marriage registration will cover this separate ISA filing in more depth; this section only flags that the process exists and is not automatic.
Translation Requirements Vary by Ward Office
Ward offices differ on exactly what a translation must show. Yokohama City and Funabashi City require a Japanese translation of the affidavit of competency and any other foreign-language document, with the translator's name identified, and both allow either partner to translate the documents themselves.2111
Funabashi's page additionally asks for the translator's phone number or address and states a three-month validity window on the affidavit itself. Chuo City, Tokyo, whose page specifically addresses foreign-national parties, requires the translator's address and name at the end of the translation.119
These municipalities are illustrative examples, not an exhaustive survey. Confirm the specific ward's translation and document-currency requirements directly before filing.21119
Cultural and Legal Differences in Name Registration
Japan's Civil Code single-surname requirement operates through the koseki system and does not mechanically apply when neither spouse has a koseki entry, so a foreign-foreign couple can generally keep or change names independently for Japanese administrative purposes.812
Each partner's home country may have its own separate legal or cultural expectations about surname change on marriage. Some require or expect adoption of a shared surname; others treat separate surnames as standard. Confirm this with each partner's own embassy or consulate rather than assuming Japan's flexibility extends to the home-country side.812