The documents, all of them, with the fine print

The official requirement is one line: documents in a foreign language need a Japanese translation attached. No certification, no credential, no agency — anywhere. You or your spouse can translate; write the translator's name and date on each translation. Paying for "certified" translation buys peace of mind, not compliance.

Originals: the koseki, your foreign marriage certificate, the tax certificates, the signed letter of guarantee and questionnaire, and the photo prints. Copies: bank passbook pages and internet-banking records (when used as financial substitutes). The 住民票の写し sounds like a copy but is itself the official city-office document. The passport is presented, not submitted, on the change-of-status route; the COE route asks for a copy.

Plan as if not: in principle, submitted materials are not returned — request the return of hard-to-reobtain originals at the time of application. In practice that request — made at the counter when you submit — is how everyone keeps their original marriage certificate. There is no retrieving documents later; the moment to ask is filing.

Japanese certificates — the koseki, both tax certificates, and the 住民票 — must be issued within 3 months of submission. The photo must be taken within 6 months. Foreign documents carry no published freshness rule (your marriage certificate doesn't expire), but a recently issued copy reads better than a decade-old one. Practical consequence: order Japanese certificates last, just before filing.

The checklist asks for neither — just the certificate issued by your national authorities, with a Japanese translation. Apostilles belong to other paperwork journeys (marrying abroad, using Japanese documents overseas). If a forum told you to apostille everything for the COE, that's imported folklore from other countries' immigration systems.

The ISA publishes no procedure for this case — we checked. What practitioners do: submit the koseki (which proves the Japanese marriage) plus a short signed statement (理由書) explaining that your country issues no certificate for marriages concluded in Japan, naming the authority that confirmed this. Some countries issue a "report of marriage" or registration of the Japanese marriage instead — if yours does, that document is the better answer. This is practice, not published rule.

Because the checklist lists both, and they prove different events: the koseki proves the marriage is valid in Japan; your country's certificate proves it's recognized where you're from. Immigration wants both legal systems aligned. The exception the ISA itself names: nationals of countries with family-register systems (Korea is the named example) may submit that register showing the marriage instead.

The checklist assumes a Japan-side household and offers no substitute — this is part of the both-spouses-abroad gap. In practice the Japan-resident relative who files and signs the guarantee provides their own 住民票, and your spouse's missing residence record is explained in a cover note (they'll register residence on return). See the spouse-abroad section of the form guide for the full picture of that route.

The checklist's own substitute list: bank statements or passbook copies, internet-banking transaction records, or an employment offer (内定) from a Japanese employer. The list is explicitly non-exhaustive. A 非課税証明書 for a zero-income year is still worth ordering — a clean record beats a missing one.

Contact the office handling your case before the deadline passes — the request letter names the section and number to call. Offices routinely work with applicants who respond: send what you have, explain what's delayed and when it arrives (a dated 理由書 helps). What turns a routine request into a denial is silence. No published rule governs extensions; responsiveness is the protective factor.

Front-loading relationship evidence — the letter, the timeline, a sensible photo set — is standard practice and matches how the system behaves: the ISA itself warns that materials beyond the published list may be requested during examination. Front-load what answers predictable questions; skip padding. A hundred chat screenshots don't say more than five well-chosen pages.

The required documents are the same — the 住民税 certificates capture self-employment income just as they do salary, because they're based on the tax return. Where freelancers stumble is having skipped filing. Supplementing with the 確定申告書 copy (the tax return itself) and bank records showing the income stream is common practice when the certificate alone looks thin.

It's not on the spouse-COE checklist. Some applicants confuse requirements with the marriage-registration stage (city halls do ask foreign spouses for birth certificates when accepting a 婚姻届) or with other countries' spouse-visa processes. For the COE: no, unless immigration specifically requests it for your case.

Yes — apply with the passport you currently hold; the checklist asks for a copy, not a long validity. The constraint comes later: the visa is issued into a specific passport, so finish any renewal before the embassy step, and carry both booklets if the old one held Japan stamps.

Substantively no — same koseki, marriage certificate, tax certificates, guarantee, 住民票, questionnaire, and photos. Mechanical differences: the change application presents your passport and residence card instead of attaching copies, skips the return envelope, and under-16s skip the photo. See the change-of-status page for that route's rules and timing.