How to Get SMS Verification Codes in Japan

If your Japan trip runs on a data-only travel eSIM, that eSIM cannot receive SMS verification codes — it has no phone number attached to it. To keep receiving bank one-time passcodes, Google sign-in codes and airline check-in texts, you need your home number to stay reachable, either by leaving your home SIM switched on for texts, by using Wi-Fi Calling where your carrier supports it, or by moving your logins to an authenticator app before you fly.

Why doesn’t my travel eSIM receive SMS codes in Japan?

Almost every eSIM sold for tourists in Japan is a data-only product. It gives your phone an internet connection over a Japanese network, but it does not issue you a phone number, so there is nothing for an SMS to be delivered to.

Ubigi states this plainly in its help centre: “You will not get a new mobile phone number with your Ubigi eSIM,” because “Ubigi provides mobile data connectivity only and does not provide any mobile phone number to make standard phone calls or text messages.”

Airalo’s guidance is the same in practice. Its help article on data-only eSIMs tells you that if your eSIM is data-only, “you can still use another line for voice and SMS” — meaning the SMS has to arrive on your home line, not the travel eSIM.

How dual SIM actually works on your phone

Modern phones can hold two lines at once, but they treat data and messaging separately, and that separation is what you are going to exploit.

Apple’s documentation for Dual SIM with an eSIM confirms both lines can handle messaging: both phone numbers can “send and receive messages using iMessage, SMS, and MMS.” But it also sets the key limit — “One number at a time can use cellular data,” and “Your iPhone can use one cellular data network at a time.”

Google describes the same split on Pixel. You choose which SIM handles data, calls and texts independently in Settings, and “Only one SIM can be the default for data.” There is one exception worth knowing: “During a phone call, all data goes through the SIM making the call.”

The fix follows directly. Data default goes to the Japanese travel eSIM; voice and SMS default stays on your home line. Your home line does not need to carry any data at all to receive a text.

Method 1: Keep your home SIM on for texts only

This is the setup most travellers should use, and it is what the eSIM providers themselves recommend.

Airalo’s help article gives the steps directly. On iOS, go to Settings > Cellular, make sure your primary line is switched on via “Turn On This Line,” set your main line as the Default Voice Line, and leave the eSIM selected for mobile data. On Android (Samsung and Pixel), go to the SIM settings, then set your primary line for calls and SMS, and keep the eSIM selected for mobile data.

The cost question is what people get wrong. Incoming SMS while roaming is often free or included, but that varies by carrier, and Airalo warns that “The data roaming may also need to be enabled depending on the requirement of your home provider. This may incur roaming charges.”

The safe configuration is: home line on, data roaming off for the home line, travel eSIM set as the data line. That way your home line is registered on a Japanese network for text delivery, but it cannot quietly spend money on background data.

What US carriers charge for this

Two examples, both from the carriers’ own pages and both current as of September 2026.

T-Mobile’s Japan roaming page lists unlimited texting on all of its consumer plans while in Japan, with data allowances that differ by plan — 30GB high-speed then 256kbps on Better Value plans, 15GB on Experience Beyond and Go5G Next, 5GB on Experience More and Go5G Plus, and unlimited 256kbps on Go5G, Magenta and One. Voice calls are $0.50 per minute across all of them, and plans outside that list are billed at $1.00 per MB of data. As of September 2026, that means a T-Mobile customer can usually leave the home line on for SMS at no extra cost.

Verizon works differently, and this is the trap. TravelPass costs $12 per day in Japan as of September 2026 ($6 per day in Mexico and Canada), and the daily charge is not something you opt into per message: “A 24-hour TravelPass session starts automatically when you use your device in a TravelPass country (e.g., make or answer a phone call, send a text or use data).” Verizon also warns that background data alone can start a session, listing “App content refreshing,” “Syncing (e.g., with email),” and “Device or app software updates.”

Verizon’s FAQ page does not state whether a purely incoming text triggers a session, so do not assume it is free. If you are on Verizon and want to avoid daily charges, turn off data roaming on the home line and confirm with Verizon before you travel.

Method 2: Wi-Fi Calling, where your carrier supports it

Wi-Fi Calling routes your home number over an internet connection instead of a cellular network, which can keep you reachable without touching a Japanese tower.

Apple’s instructions are short: go to Settings, tap Cellular, select your line if you have more than one SIM, turn Wi-Fi Calling on, tap Enable, and confirm your address for emergency services. Apple notes that “If Wi-Fi Calling is available, you’ll see ’Wi-Fi’ in the status bar,” and that you need to “make sure that your carrier offers Wi-Fi Calling.”

The important caveat is that Apple’s page describes how to turn the feature on, not whether it will work from Japan — that is a carrier decision, and enabling the setting for voice does not by itself mean SMS will be delivered over Wi-Fi Calling.

T-Mobile does address the abroad case. Its international roaming support page says “You can still use Wi-Fi for calls and text; additional charges may apply,” and prices Wi-Fi calls from 215+ countries at $0.50 per minute, with no charge for Wi-Fi calls to the US, Mexico and Canada — as of September 2026. That same page notes that if you block all international roaming, “you’ll no longer be able to call, text or use data for the selected line while roaming outside the US.”

Turn Wi-Fi Calling on and test it at home, on your own home Wi-Fi, before you fly. If it does not work in your own living room, it will not start working in a Japanese hotel.

Method 3: Move your logins to an authenticator app

This is the only method that removes the dependency on SMS entirely, and it is the one to do first because it costs nothing.

Google Authenticator generates one-time codes on the device itself. Per Google’s documentation, the app “can generate one-time verification codes for sites and apps that support Authenticator app 2-Step Verification,” and crucially, “You can still generate codes without an internet connection or mobile service.”

That is the whole argument. A code generated on your phone does not care whether your home line is reachable, or whether Japanese roaming worked.

Google also documents syncing: “When you sign in to your Google Account within Google Authenticator on a new device, your codes are automatically synced to this device.” Backup is optional — you can use the app without it — and if you use it without a Google Account you can still move codes manually by exporting them as QR codes and scanning them on the new device.

One warning from Google’s own page that matters if you carry two phones: if you have synced your codes, deleting them on one device deletes them “from all devices where your codes are synced.”

Switch your Google account, your email, and any service that offers it to authenticator-based verification at least a week before departure. Banks are the common exception — many still insist on SMS to a registered number, which is exactly why Method 1 still matters.

Method 4: A Japanese number that receives SMS

If you need a Japanese phone number — for a domestic service, a reservation system, or a longer stay — some providers sell voice-capable SIMs and eSIMs with a real Japanese number rather than data only.

Mobal, for example, sells a voice-only eSIM with a real 070, 080 or 090 Japanese number on the docomo network, advertised at ¥1,430 per month as of September 2026, with free incoming calls and SMS and outgoing calls and texts charged per minute or per message. Its access code is listed at ¥4,950, discounted to ¥4,455 as of September 2026. Mobal also offers voice-plus-data eSIMs with plans from 1GB to 200GB per month.

Be clear about what this does and does not solve. A Japanese number receives codes sent to that number. It will not receive the code your American bank sends to your American number — for that, you still need Method 1, 2 or 3. Treat a Japanese number as a tool for Japanese services, not as a replacement for your home line.

Comparison: which method should you use?

What to do the week before you fly

Work through this in order. Each step reduces how much the next one has to carry.

• Move every account that supports it from SMS codes to an authenticator app, and confirm you can generate a code with the phone in aeroplane mode.
• List the accounts that still require SMS — usually banks and government services — and note which number each one texts.
• Check your home carrier’s page for Japan specifically: is roaming SMS included, or does receiving a text start a daily charge?
• Turn on Wi-Fi Calling and place a test call over your home Wi-Fi.
• Update the phone number on file with your bank if it is an old one you no longer carry.
• Save at least one backup code per critical account somewhere you can reach without your phone.

How to configure your phone on arrival in Japan

Once you land and install the travel eSIM, the settings should end up like this.

• Mobile data: the Japanese travel eSIM.
• Default voice line: your home number.
• SMS / messages: your home number.
• Data roaming on the home line: off.
• Data roaming on the travel eSIM: on — travel eSIMs generally roam onto a Japanese network and need this enabled.

On iPhone, Apple notes a messaging quirk worth remembering: “If you start an SMS/MMS Messages conversation using one line, you can’t switch the conversation to your other line; you need to delete the conversation and start a new conversation using the other line.”

FAQ

Can I receive SMS on a data-only Japan eSIM?

No. Data-only eSIMs have no phone number, so there is no number for an SMS to reach. Ubigi’s help centre states that its eSIM does not come with a mobile phone number for standard calls or texts, and Airalo’s guidance is that you use another line for voice and SMS.

Will I be charged for receiving a text in Japan?

It depends on your carrier. T-Mobile’s Japan roaming page lists unlimited texting on its consumer plans as of September 2026. Verizon starts a $12-per-day TravelPass session when you use your device in a TravelPass country, and its FAQ does not specify whether a purely incoming text triggers one — check with your carrier before you rely on it.

Does WhatsApp or iMessage solve this?

Only partly. Internet-based messaging runs fine over your travel eSIM’s data, and Ubigi points travellers to VoIP apps for calls and messages. But a bank sending a one-time passcode sends it as an SMS to your registered number, and no messaging app intercepts that.

Should I turn off my home SIM completely to avoid charges?

Not if you need SMS codes. Switching the line off means it cannot register on a network and cannot receive texts. The middle ground is to leave the line on for voice and SMS while turning data roaming off for that line, so it stays reachable without spending on data.

Is an authenticator app safer than SMS?

For travel purposes it is more reliable, because Google documents that codes can be generated “without an internet connection or mobile service.” Whether it is more secure for your specific accounts is a separate question your bank or provider decides — some services still require SMS regardless of what you would prefer.

The short version

Your travel eSIM handles data; your home number handles verification codes. Set the eSIM as your data line and your home SIM as your voice and SMS line with data roaming switched off — then reduce how much you depend on that by moving every account you can to an authenticator app before you leave.

The figures above are what the carriers published as of September 2026. Check your own carrier’s Japan page before departure rather than assuming your plan matches these examples.

Sources

• Using Dual SIM with an eSIM — Apple Support (accessed 2026-09-02)
• Make a call with Wi-Fi Calling — Apple Support (accessed 2026-09-02)
• How to use dual SIMs on your Google Pixel phone — Google Pixel Phone Help (accessed 2026-09-02)
• Get verification codes with Google Authenticator — Google Account Help (accessed 2026-09-02)
• How can I receive SMS and calls while connected with my data-only eSIM? — Airalo Help Center (accessed 2026-09-02)
• What will be my Ubigi eSIM mobile phone number? — Ubigi Help Center (accessed 2026-09-02)
• International Roaming Plans for Japan — T-Mobile (accessed 2026-09-02)
• International roaming services — T-Mobile Support (accessed 2026-09-02)
• Verizon TravelPass FAQs — Verizon Support (accessed 2026-09-02)
• eSIM Japan: eSIM with Japanese Phone Number — Mobal (accessed 2026-09-02)