The short answer

A long stay is not simply a short stay with more gigabytes. At some point you stop buying a travel product and start applying for monthly service. What you can apply for may be decided by the identity document in your bag rather than by the length of the trip.

First decide whether data is enough. If you need a Japanese 070, 080 or 090 number, that requirement outranks duration.

When a stay stops being a travel-product purchase

Providers can run two different services under one brand. A travel product is bought once, used and allowed to expire. Monthly service is a recurring contract with an application behind it.

Sakura Mobile is one current example. Its official chooser separates travel service for stays below 90 days from monthly service for stays above 90 days. The travel SIM and eSIM are data-only. Monthly service includes data-only and voice-and-data choices.

That 90-day line is the provider's product and billing structure, not a legal ceiling for every SIM in Japan. Other products can use different terms. The durable lesson is that a longer stay may change the category of service and the application behind it.

Data, or a Japanese phone number?

It sounds like a preference. In Japan it decides your paperwork.

Japanese official guidance separates mobile voice service from a data-only SIM that cannot carry voice. The data-only service sits outside that voice-service identity law. An international travel eSIM issued by an overseas operator also follows a different route from a Japanese mobile voice contract.

This describes what the law requires. It does not promise what a company will ask for. Mobal says its own data-only eSIM does not need an ID upload. Sakura's monthly data-only application asks for documents. Both procedures can coexist because a provider may ask for more than the voice-service law compels.

Decide whether any part of the stay needs a Japanese number and SMS. First use the short-stay phone-number test to separate data, home-number OTP and a real Japanese line. Domestic ticketing is one concrete case: our ticket guide then checks the exact event route.

If you need a number, your documents decide the route

If columns are cut off, scroll sideways. Keyboard: focus the table, then use Left/Right Arrow keys.

What you can presentPublished exampleWhat to confirm
Residence card with registered address, Japanese driving licence or My Number cardSakura says these documents can support a fully online monthly voice-eSIM process.The current address, accepted document and activation timing for the exact order.
Passport without a Japanese addressSakura directs this route to physical pickup and a face-to-face check.Which counter, its hours and whether pickup happens after arrival.
Qualifying Japanese-address IDMobal publishes a Japan Post handoff for voice SIMs and voice-eSIM access codes.The address match, the first instruction letter and the ID needed for final delivery or collection.
Passport collection in JapanMobal publishes collection using the purchaser's passport and order confirmation.The purchaser must appear; another person cannot collect on their behalf.

These are current examples of how two providers handle the same problem. Neither is a recommendation or a description of the whole market. For the details that decide an order, the operator's current page is the authority and this page is not.

Work out your own route

About 60 days

Check the ceiling instead of assuming

Find the maximum term and extension policy of the specific plan. If the answer is another purchase, confirm what that second order requires while you are already in Japan.

More than 90 days

Plan for monthly service

Ask which documents are accepted, whether the route finishes online or at a counter and where any physical handoff goes.

Any duration

If a Japanese number is required

The number question outranks the day count. Solve the identity and handoff route first, then choose the data allowance.

The digital-nomad case

Japan's published designated-activities status for digital nomads lasts up to six months, is not renewable and does not issue a residence card. That creates an unusual combination: the stay can sit beyond a provider's travel-product range while the document that opens one online monthly route is unavailable.

With the two procedures checked here, a passport-based collection route remains the practical branch. Ordering and choosing a collection point can happen before travel; the in-person identity step happens after arrival. This is connectivity guidance, not immigration advice. Confirm the status itself with the Immigration Services Agency or a qualified adviser.

The imported-device question is not a SIM-plan limit

Japan expects radio equipment to meet its technical standards, shown by a conformity mark. The Ministry of Internal Affairs and Communications provides a temporary-use exception for qualifying equipment brought from abroad. For the wireless-LAN and Bluetooth side, that exception is limited to 90 days from entry.

This is not a universal day-91 cutoff for every foreign phone. It matters when imported equipment lacks the Japanese conformity mark and is relying on the temporary exception. A device carrying the mark is outside that specific problem. The official page describes the exception; it does not support inventing a penalty or predicting enforcement.

The mobile part also has its own conditions, including the overseas-carrier and roaming relationship described by the ministry. If those conditions are unclear, ask the provider or ministry rather than treating a SIM comparison as legal advice. Keep this question separate from the product's validity period: the two 90-day figures have different sources and different answers.

Five things to settle

  1. Confirm the handset before the plan. A locked phone or unsupported regional variant cannot be fixed by a longer contract.
  2. Ask which document is accepted from you. Do not stop at a provider's general list.
  3. Locate the final handoff. Online completion, address-matched post and passport pickup are different routes.
  4. Find what starts validity. Purchase, installation, activation and first Japanese signal are not interchangeable.
  5. Escalate the device-conformity question. If the stay crosses 90 days and the mark is uncertain, use the official or provider channel rather than a travel comparison.

If the plan is already bought, the state-based activation guide separates order delivery, installation, activation and first connection.

Why we recommend this: decision evidence

What changes when a Japan stay becomes a monthly-service decision

Duration is only the first branch. A Japanese phone number, the document in hand and the imported device's conformity status can each change the usable route.

If columns are cut off, scroll sideways. Keyboard: focus the table, then use Left/Right Arrow keys.

DecisionVerified findingSource basisWhat it changes for the traveller
Does Japanese mobile voice identity law cover data-only SIMs?The ministry says a data-only SIM that cannot provide mobile voice service is outside that law. This does not prevent a provider from requesting documents under its own application policy.MIC identity-verification Q&A, JapaneseTreat data-only as the lighter legal route, then still read the selected provider's actual document requirements.
Does every foreign phone face a universal day-91 cutoff?No. The 90-day limit belongs to the temporary-use exception for imported wireless-LAN equipment. It matters when equipment lacks the Japanese conformity mark and relies on that exception.MIC temporary-use guidance, JapaneseCheck the device mark and circumstances instead of treating the SIM plan's term as an answer to the equipment question.
Can a longer Sakura Mobile stay remain on the same travel product?Sakura publishes travel service for stays below 90 days and recurring monthly service for stays above 90 days, with both voice-and-data and data-only monthly choices.Sakura Mobile product chooser, EnglishCheck the exact product ceiling and application route before assuming that another travel plan is the only extension method.
Is a Japanese voice eSIM always an instant digital delivery?No. Sakura and Mobal publish different online, address-matched delivery and in-person collection routes. The usable route depends on the provider and the document the purchaser can present.Sakura Mobile and Mobal official help, EnglishResolve the accepted document, Japanese-address requirement and collection point before treating eSIM format as instant access.
Do all data-only providers waive document checks?No. Sakura's monthly data-only application requests documents, while Mobal says its own data-only products do not require an ID upload.Sakura Mobile and Mobal official application help, EnglishDo not convert a legal scope distinction into a promise about the selected provider's application.
What should a long-stay reader decide before comparing data allowances?Decide whether data is enough, identify the accepted document and handoff route, and keep the imported-device question separate from the plan duration.Japanese official rules and the two operator procedures read togetherAvoid paying for a plan that cannot provide the required number or cannot be handed over through the reader's actual document route.

This ledger records source-backed decisions, not personal experience. Field tests are labelled separately.

Why there is no “best long-stay SIM” table here

The operators on this page appear as examples of different procedures. No ranked provider, product price or compensated link is shown. A commercial recommendation stays withheld until the exact product, document route, delivery, cancellation and affiliate terms are checked together.

Review dates and complete update history

Editorial maintenance In schedule

What was checked and what changes next

First published
Reviewed
Next scheduled review
This review covered
MIC and Immigration Services Agency guidance plus current Sakura Mobile and Mobal application procedures.
Latest material change
: Separated travel-plan duration, Japanese-number paperwork, provider identity routes and the conditional imported-device rule.

Editorial responsibility

One accountable owner-editor

Japan, Booked. is owner-operated and edited from Japan. The same editor is responsible for the guide's Japanese- and English-language source checks, traveller-facing judgement and correction record. No unapproved personal name, biography or credential is being implied.

Public change log

Update history

  1. Published the long-stay document-route guide

    Separated travel-plan duration, Japanese-number paperwork, provider identity routes and the conditional imported-device rule.

A material operator, organiser or product change triggers an earlier review. Reader reports are treated as leads and checked against the rule owner before publication. Read the update and correction policy. See every guide's review schedule. Suggest an improvement to this guide.

Official sources and what each confirms

Official sources

  1. JapaneseGovernment official guidance
    MIC: temporary use of devices brought into Japan

    Established: The temporary-use exception for imported wireless-LAN equipment is limited to 90 days from entry. The ministry directs a user beyond that period to equipment carrying the Japanese technical-conformity mark; the condition is not a universal rule for every foreign phone.

    Checked
  2. JapaneseGovernment official guidance
    MIC: mobile voice-service identity-verification Q&A

    Established: The identity-verification law covers mobile voice service. A data-only SIM that cannot provide mobile voice service sits outside that law, while providers may still impose their own application checks.

    Checked
  3. JapaneseGovernment official guidance
    Immigration Services Agency: digital-nomad designated activities

    Established: The published digital-nomad status allows a stay of six months, is not renewable and does not issue a residence card. Connectivity guidance must therefore keep a passport-based provider route available.

    Checked
  4. EnglishProvider official help
    Sakura Mobile: travel or monthly service chooser

    Established: Sakura presents travel service for stays below 90 days and recurring monthly service for stays above 90 days. The split is the provider's product and billing structure, not a universal legal cutoff.

    Checked
  5. EnglishProvider official help
    Sakura Mobile: monthly voice eSIM identity route

    Established: A passport or another document without a current official Japanese address requires physical pickup and a face-to-face check. A residence card with registered address, Japanese driving licence or My Number card can support an online process.

    Checked
  6. EnglishProvider official application guidance
    Sakura Mobile: monthly data-only application procedure

    Established: Sakura's monthly data-only service asks for application documents even though data-only service is outside the mobile voice identity law. Its published routes include residence-card delivery and passport pickup.

    Checked
  7. EnglishProvider official help
    Mobal: ID requirements for voice products

    Established: Mobal's voice-capable SIM/eSIM products use either ID-matched delivery or collection in Japan with the purchaser's passport and order confirmation. Its own data-only products do not require an ID upload.

    Checked
  8. EnglishProvider official help
    Mobal: Japan shipping and delivery procedure

    Established: Japan delivery for a voice SIM or eSIM access code is not instant: Japan Post first sends instructions and the named user must complete delivery or collection using qualifying Japanese-address ID. Mobal says a passport is not accepted for this route.

    Checked

How we review

Visible sources.
Clear conditions.

Read the official sources behind each decision.

How we review