Daily Life Lessons · Mobile Phones
Be able to handle the identity check and review the contract terms yourself when getting a mobile phone contract, know about the system for cancelling within 8 days, and avoid getting involved in crimes such as handing your SIM card or phone to others.
When you get a mobile phone contract, the carrier checks your identity based on the law (the Mobile Phone Improper Use Prevention Act / 携帯電話不正利用防止法). Foreign nationals use their residence card (在留カード) or similar documents. From April 2026, the method of sending a photo of your ID document for online contracts was abolished (with a transitional measure until September 30, 2026) and is being replaced by methods such as reading the IC chip (the method differs by carrier).
Before signing, carefully check the price plan, contract period, cancellation costs and how you will pay for the device. There is an "initial contract cancellation" system (初期契約解除) that lets you cancel the telecommunications service contract within 8 days from the day you received the contract documents (the device purchase is often not covered, and fees such as the administrative fee still apply). Major mobile carriers and some others instead have a "confirmation measure" (確認措置), under which you can cancel, including the device, only if the signal conditions were poor or the explanation was insufficient.
Do not sell or give the mobile phone or SIM card you contracted to another person without the carrier's permission. It may be used for crime, and you may be punished. When you return to your home country, cancel your contract.
携帯電話（けいたいでんわ）を 契約（けいやく）する とき、在留カードなどで 本人確認（ほんにんかくにん）を します。
契約の 前に 確認： - 1か月の 料金 - 契約の 期間 - やめる ときの お金 - 電話（たんまつ）の 代金
契約書（けいやくしょ）を もらってから 8日以内なら、契約を やめられる ことが あります（電話の 代金や 手数料は 戻らない ことが あります。やめられる 条件は 会社で ちがいます）。
SIMカードや 電話を 人に 売ったり、あげたり しては いけません。犯罪（はんざい）に なります。 帰国（きこく）する ときは、解約（かいやく）しましょう。
What is the main document foreign nationals use for the identity check when getting a mobile phone contract?
The identity check is done based on the law. Foreign nationals use their residence card or similar documents.
What should you check before signing a contract?
So you don't have problems later, check the fees and cancellation conditions carefully.
When can you use initial contract cancellation?
You can cancel the telecommunications service contract within 8 days from the day you received the documents. The device purchase is often not covered, and major mobile carriers and some others apply a "confirmation measure" instead.
What should you do if someone says "I'll buy your SIM card"?
Transferring a contracted mobile phone or SIM to another person without the carrier's permission is prohibited by law and it may be used for crime.
What should you do when you return to your home country?
Cancel lines you no longer use. If you give them to others, they may be used for crime.
Q. If I can't go to a store, can I sign up online?
A. In some cases, yes. However, the identity check method changed from April 2026 (with a transitional measure until September 30), and methods such as reading the IC chip are now required. The documents and methods you can use differ by carrier, so check the carrier's website before applying.
Q. Where can I get help with contract problems?
A. First, contact the carrier you signed with. If that doesn't solve it, you can call the consumer hotline "188" to consult a nearby consumer affairs center or similar.
Q. What if I get an SMS saying "We failed to deliver your package"?
A. Do not tap the link in the message. It is a fake SMS pretending to be from a delivery company, and your personal information may be stolen or a malicious app may be installed. If you are worried, check using the official app or website.
This practice tool asks questions in random order (it works when JavaScript is enabled). You can still read all the questions and explanations above without it.
Systems and procedures may differ depending on the city, ward, town or village where you live and on the time of year. Please check the latest information from your local government or the relevant organizations.
Content checked on: 2026-09-28
This page is a translation of the Japanese original. If the translation and the original differ, the Japanese version takes precedence. View the Japanese original