Mobile Operators & SIM Cards in Japan

Checked September 29, 2026 · Sources listed at the end of the page

Four network operators, NTT Docomo, the KDDI group, SoftBank and Rakuten Mobile, hold about 82% of Japan's mobile contracts, and virtual operators (MVNOs) the rest, according to the Ministry of Internal Affairs and Communications (MIC). A Japanese SIM that can make calls or send texts requires an identity check, for which visitors can use their passport; the two visitor eSIMs below are data-only.

Mobile networks in Japan

Share of mobile lines by operator, as of end of June 2026 (share of mobile contracts). Sources are listed at the end of the page.

Operator	Group	Share
NTT Docomo		32.2%
KDDI group	KDDI, Okinawa Cellular, UQ Communications	26.5%
SoftBank		19.1%
Rakuten Mobile		3.8%
Virtual operators (MVNOs)	Various	18.6%

In MIC's figures, the "KDDI group" covers KDDI, Okinawa Cellular and UQ Communications.

Buying a SIM card in Japan as a visitor

Foreign visitors who take out a mobile phone or SIM with a Japanese carrier must go through identity verification if the SIM can be used for calls or SMS text messages.
Visitors can use their passport for this identity check.
The rules don't distinguish by how you pay: prepaid phones and SIMs are also subject to identity verification.
Since April 1, 2026, a phone or SIM contract signed online must in principle be verified by reading the IC chip in the customer's ID document.
For online contracts, sending a copy of an ID document or a picture of a photo ID is no longer accepted.
For contracts signed in a store, the new identity-check rules take effect on April 1, 2027, though some carriers have already changed how they check ID in their shops.
Under the law, the data-only SIMs that require identity verification are those that can send and receive SMS.
SIMs without SMS are outside the legal rule, but carriers often run the same ID check anyway as an anti-fraud measure.
From April 2027, the identity-check rules change again, and data-only SIMs also become subject to identity verification.
MIC notes that short-stay foreign visitors can also be covered, for example when using a data SIM for tourism or business.
Japan's mobile phone improper-use prevention law forbids giving a working phone or SIM to anyone other than a relative without the carrier's consent.

Bring your passport if you want a Japanese SIM with calls or texts: visitors can use it for the identity check the rules require, prepaid SIMs included.

Prepaid offer examples

Prices from each operator's own website or announcements, checked on September 29, 2026. Offers change often, so confirm before you buy.

povo (KDDI)

Japan SIM (online eSIM), 20 GB / 30 days

JPY 2700

Price as of March 2026 (KDDI announcement)

Validity:: 30 days, starting when you buy the pack (account ends 90 days after eSIM activation)
Data:: 20 GB; other packs from JPY 600 (3 GB / 3 days)
Includes:: Data only: no calls, no SMS. Tax included. No photo ID; needs a credit card and a US (or other listed) phone number that can receive a verification SMS

See the offer on povo (KDDI)'s site

IIJ (Docomo network)

Japan Travel SIM/Digital (eSIM), 10 GB

JPY 3280

Price as of November 2025 (IIJ announcement); IIJ says to confirm the price at the store

Validity:: 30 days from the start of use
Data:: 10 GB; plans from 3 GB (JPY 2,480) to 55 GB (JPY 5,780)
Includes:: Data only, on NTT Docomo's 4G network. Bought at FamilyMart multifunction copiers and paid at the register; price as announced in November 2025, listed as tax-free

See the offer on IIJ (Docomo network)'s site

Using your US phone in Japan

Whether your US plan covers Japan, and at what cost, depends on the plan, so check your carrier's international page before you go. Our guide to using your US phone abroad covers roaming, Wi-Fi calling and bill surprises.

To call Japan from the US, dial 011 + 81 + the number: see how to call Japan and the Japan phone number format.

FAQ

Do I need a passport to buy a SIM card in Japan?

Foreign visitors who take out a mobile phone or SIM with a Japanese carrier must go through identity verification if the SIM can be used for calls or SMS text messages. Visitors can use their passport for this identity check. The rules don't distinguish by how you pay: prepaid phones and SIMs are also subject to identity verification.

What changed on April 1, 2026 for SIM and eSIM contracts in Japan?

Since April 1, 2026, a phone or SIM contract signed online must in principle be verified by reading the IC chip in the customer's ID document. For online contracts, sending a copy of an ID document or a picture of a photo ID is no longer accepted. For contracts signed in a store, the new identity-check rules take effect on April 1, 2027, though some carriers have already changed how they check ID in their shops.

Do data-only eSIMs for tourists require ID in Japan?

Under the law, the data-only SIMs that require identity verification are those that can send and receive SMS. SIMs without SMS are outside the legal rule, but carriers often run the same ID check anyway as an anti-fraud measure. From April 2027, the identity-check rules change again, and data-only SIMs also become subject to identity verification. MIC notes that short-stay foreign visitors can also be covered, for example when using a data SIM for tourism or business. No photo ID is required to register for povo's Japan SIM.

Which is the biggest mobile operator in Japan?

NTT Docomo held 32.2% of mobile contracts at the end of June 2026 (38.7% counting the lines it provides to virtual operators). The KDDI group held 26.5% (31.8% counting lines provided to virtual operators). SoftBank held 19.1% (24.7% counting lines provided to virtual operators).

Which network do IIJ SIMs use?

Among SIM-card plans sold by virtual operators, Internet Initiative Japan (IIJ) had the largest share, 24.5%, at the end of June 2026. IIJ's Japan Travel SIM/Digital is a data-only prepaid eSIM for visitors that runs on NTT Docomo's network across Japan.