How This Site Is Made

Japan Phone Guide is written and maintained by one person, under the handle “dasmo”. It began as personal notes made while getting a phone in Japan as a foreign resident — working out which procedure applied, what documents were needed, and why the counter total came out higher than the plan price.

It is not a company, a carrier, a shop or an agency, it is not affiliated with any of them, and it sells nothing — no contracts, devices or SIMs — and takes no commission on sign-ups. That matters because it means there is no reason for a page here to steer you toward one carrier or one option over another. The formal operator and independence disclosure is on the

Operator & privacy page.

Every guide starts from primary sources, in this order of preference:

• The carrier's own official pages — Japanese-language support pages, plan pages, and the actual terms and conditions (規約) and important-matters documents (重要事項説明), not the marketing headline.
• Government and public-body guidance — the Ministry of Internal Affairs and Communications (総務省), the Consumer Affairs Agency (消費者庁) and the National Consumer Affairs Center (国民生活センター).
• Direct observation — going through the procedure, reading the paperwork, and noting where the steps and the wording actually trip people up.

Each guide page ends with a “Sources” list linking the official pages it draws on. Where a figure is an example, or where it varies by carrier, device or date, the page says so rather than presenting one number as universal.

Carrier names, plan names and other proper nouns are kept in their official form. Nothing here is presented as the position of a carrier or a public body — only as a reading of what their published material says.

Plans, prices, campaigns, required documents and support rules in Japan change often. Because of that, the site is built to point you at the official source rather than ask you to trust a number printed here.

• Every guide shows a “last checked” date. The most recent site-wide review was 2026-08-29 (JST).
• When a rule or a price changes, the affected pages are updated and the date is moved forward.
• The advice throughout is: confirm the current figure on the carrier's official page before you decide or sign.

If you find something out of date or wrong, telling me is the fastest way to get it fixed — see below.

• It is not advice. Nothing here is legal, financial, tax or immigration advice. For a decision that matters, confirm with the official source and, where needed, a qualified professional.
• It is not affiliated with any carrier, shop or agency, and it does not represent them.
• Examples and sample figures are illustrative. They are there to show how a number is structured, not to quote today's price.

Full disclaimer

The site is published in 20 languages under /<language>/. English and Japanese are written and edited by hand. The other 18 languages — the menus, labels and the guide text — are machine-translated, then passed through a domain glossary so that terms like “carrier”, “plan” and “residence card” come out consistently. Proper nouns (carrier and plan names) are kept in their official form and are not translated.

Machine translation can be awkward or, occasionally, wrong. If a translated sentence does not read right, the English or Japanese version of the same page is the one to rely on. Corrections to any language are welcome.

Corrections, missing information and questions are all welcome by email:

dasmomitsumori@gmail.com

This is a personal project run in spare time, so a reply may take some days. Please do not send identity documents or contract details by email.