Best eSIM for Japan: Plans, Pricing & User Experiences

Whether you’re navigating Osaka streets, looking for the best sushi in Tokyo, or sharing photos with friends and family, you’ll need a reliable mobile connection in Japan.

Instead of purchasing physical SIMs or expensive roaming packages, you can opt for an eSIM (digital SIM card) for extra convenience, multiple profile support, and flexibility. The only problem is the abundance of options, so choosing the right package can be overwhelming and time-consuming.

To save you from hours of research and help you select the best eSIM for Japan, we’ve reviewed five popular providers and their offers, comparing their coverage, prices, and customer reviews.

How To Choose the Best eSIM Card for Japan: Criteria To Focus On

To find a provider and package that delivers the most value, focus on the following criteria:

1. Coverage: Choose an eSIM that offers reliable coverage throughout Japan, not only in major cities.
2. Data allowance: Opt for an eSIM with unlimited data if you’re planning a longer trip or wish to keep using the eSIM card upon return.
3. Security and privacy: Select an eSIM provider with clear and strict security and privacy policies, as well as advanced options that ensure data protection and minimize the risk of network-level threats.
4. Ease of activation: Go for an eSIM that is easy to set up and use.
5. Customer experiences: Find an eSIM with positive customer reviews that confirm its reliability and value.

Which eSIM Is Best for Japan? 5 Options Reviewed

With the above criteria in mind, we’ve analyzed dozens of eSIM providers for Japan and shortlisted the best ones:

1. Cape
2. Ubigi
3. Roamify
4. Airalo
5. Sakura Mobile

1. Cape

Unlike some other options on the list, Cape isn’t an eSIM marketplace but a mobile carrier that operates on eSIM-compatible devices. As such, Cape doesn’t cater only to travelers; it’s an ideal solution for anyone who wants to use eSIMs in their everyday lives or for business purposes.

The carrier’s eSIM offers excellent coverage worldwide, including Japan. For this country, Cape’s plan encompasses the following:

• Unlimited data
• Unlimited voice calling
• Unlimited texting

Since Cape is based in the United States, the service must be activated before you leave the country. The process is simple. Once you sign up, Cape sends you an activation kit with a step-by-step guide that even those who aren’t tech-savvy can easily follow.

Cape offers a single plan that works both in the U.S. and worldwide, so you don’t have to worry about buying a new eSIM every time you travel internationally. The plan costs $30 per month and has no hidden charges. There are no contracts, so you can cancel the service at any time, which can be convenient for short trips.

Besides travel convenience, Cape offers privacy and security by design, which is its key advantage over other eSIM options. It also:

• Maintains complete control of its eSIMs to ensure maximum credential protection
• Relies on its own advanced infrastructure instead of legacy, trust-based networks
• Minimizes data collection to safeguard users’ privacy
• Offers advanced features for minimizing network-level threats

As such, Cape offers both reliability and high security, so you can stay connected in Japan without worrying about external threats.

2. Ubigi

Ubigi is a global mobile connectivity service provider that offers eSIM plans worldwide, including Japan.

Ubigi offers three types of plans:

You can install an eSIM in two ways:

1. Via the Ubigi app
2. Using the provided QR code

Ubigi provides detailed installation guides for both methods; however, some users have found them difficult to follow. One user in particular struggled with setting up the eSIM, which left them without data upon arrival in Japan. Another potential issue often brought up by users is an unstable or non-existent connection, even in areas with a strong signal.

Ubigi lacks in the security and privacy department. Its website doesn’t mention concrete security measures the company takes to keep user data safe. Considering that Ubigi collects and processes a long list of personal, financial, and traffic usage information, the lack of detail on security protocols is concerning.

3. Roamify

Roamify is a telecommunications company known for its broad range of affordable eSIM plans. The company covers Japan and offers two types of packages:

1. Unlimited: You get unlimited data and choose the desired validity period. The maximum is 30 days, but you can renew your plan if necessary.
2. Data: You pick the number of GB you want. Options range from 10 GB to 1 TB.

Pricing depends on the selected plan, but here are some examples:

• Unlimited data for five days: $7
• Unlimited data for 30 days: $50
• 10 GB for four days: $6
• 300 GB for 30 days: $60

Roamify offers calls and texts for some plans, though these are not available for Japan.

The eSIM installation process is straightforward. You pick a plan, pay, and receive a QR code via email, which you’ll need to scan to activate the eSIM.

User experiences with Roamify are mostly positive, but some mention that the service didn’t work and that they were unable to reach customer support and get a refund despite many attempts. One specific user mentioned that their Roamify eSIM didn’t work in Japan and that they ended up purchasing an eSIM from a different company.

Regarding security and privacy, Roamify has a transparent privacy policy that outlines the security measures the company employs to protect users, including Secure Socket Layer (SSL) encryption, firewalls, and role-based access controls. The company itself states that it can’t guarantee security. Considering Roamify’s extensive data collection policy, this may be concerning for privacy-oriented users.

4. Airalo

Airalo is an eSIM marketplace that collaborates with mobile networks worldwide, offering eSIMs for over 200 destinations, spanning from Europe to South America. In Japan, Airalo works with the following two networks:

1. SoftBank
2. KDDI

There are two types of packages available:

1. Standard: You choose the number of GB and validity
2. Unlimited: You choose the validity and get unlimited data for that period

If your data allowance or validity runs out, you can always top up your plan to maintain connectivity.

According to the website, the installation process is straightforward. You can activate your eSIM via the Airalo app or by scanning the QR code sent to you via email. Airalo even has detailed guides for iOS and Android devices to help you complete the process within minutes. User reviews, however, tell a different story. Many struggled with installing their eSIM due to unclear instructions.

Those who managed to set it up often had difficulties connecting to the local network. Although this isn’t a universal experience, the number of such reviews is concerning.

Like many other eSIM marketplaces and providers, Airalo doesn’t prioritize minimal data collection. Some of the information the company collects is listed below:

• First and last name, email address, location
• Data about your browser, operating system, IP address, and preferences (such as language, currency, and airport for departures)

While Airalo has a Trust Center that provides details on the security measures intended to protect your data, access to it must be requested, and the lack of transparency could deter users.

5. Sakura Mobile

Sakura Mobile is a Japanese company offering physical SIM cards and eSIMs primarily to tourists.

The company offers data-only eSIMs with fast 4G/5G data and hotspot support. The data is unlimited, and you can select a validity period that aligns with your arrival and departure dates. Prices depend on the selected option; below are several examples:

• 15 days with 4G and 5G: Around $48
• 15 days with 4G: Around $42
• 7 days with 4G and 5G: Around $32
• 7 days with 4G: Around $27

“Unlimited” data plans with only 4G data have a limitation: speed will be limited after 3 GB of data per day. Plans that offer 4G and 5G support typically include unlimited high-speed data, so heavy users should consider this before selecting a package.

The setup process is easy, as confirmed by reviews. Users report that the installation instructions are clear and precise. Another advantage of Sakura Mobile is customer support because the team is responsive and helpful, and users are generally thrilled with the level of service they receive.

When it comes to privacy and security, Sakura Mobile has a privacy policy that discusses what information it collects and why, but it’s not particularly detailed. In terms of security, the company mentions only SSL encryption, which doesn’t provide enough protection against external threats.

What Is the Best eSIM for Japan Travel in 2025?

All eSIM providers we’ve discussed have received many positive reviews and can reliably support the needs of most travelers. The option that stands out is Cape, as the only provider on our list that focuses on security and privacy. In addition to offering superb coverage, Cape:

• Controls how your data is collected, handled, and stored to minimize exposure and maximize privacy
• Needs only your phone number to provide services
• Stores your data for the minimum amount of time possible
• Monitors signal activity to prevent hackers from abusing protocols and impersonating you

Considering its strong built-in defenses, Cape is an excellent option for any privacy-conscious traveler seeking to establish network connectivity abroad with minimal security risks.

Meet Cape: The Secure Carrier Designed for Today’s Threats

We share the most intimate details of our everyday lives with our cell phones. In order to stay connected, our cell phones share that information with local cell networks, and in turn, those cell networks share our data with each other.

While this system is what makes connectivity possible, it was also built with interoperability as its priority, rather than security. The global cell network is vulnerable to a number of threats, as seen through headlines about major carrier data breaches we see time and time again. When major carriers aren’t losing our sensitive personal data in breaches and hacks, they’re actively selling it to ad networks, data brokers, and third parties.

At Cape, we believe that privacy and security shouldn’t have to be sacrificed for connectivity. That’s why we built our service with privacy principles and security features at its core, including:

1. Minimal Data Collection

Cape eliminates the risk of your sensitive data falling into the wrong hands by not even asking for it. When you make your Cape account, we don’t ask for your name, address, or SSN. We only collect the information that’s necessary to provide the service, and we retain it for the least amount of time possible.

2. SIM Swap Protection

During account creation, you receive a unique 24-word phrase that generates a private key tied to your phone number. This pass phrase is required to move your number to a new device or carrier. Nobody else, not even us at Cape, has access to the phrase, meaning there’s absolutely no way for bad actors to transfer your number to their device, effectively nullifying the possibility of SIM swapping.

3. Disappearing Call Logs

Your phone stores an incredible amount of data, which can be accessed through call and text records. Most mobile carriers store your call and text metadata for years, which can easily fall into the wrong hands.

Cape is built to forget, meaning we delete Call Data Records (CDRs) after just 1 day, ensuring nobody can see who you texted or called, track where the communication took place, or access the sensitive information within CDRs.

4. Identifier Rotation

All SIM cards are accompanied by International Mobile Subscriber IDs (IMSI). These function as unique identifiers devices use to register with cellular networks. Traditional telcos assign fixed IMSIs to user accounts, meaning the carriers, advertisers, hackers, and other bad actors can exploit them to identify and track your device.

Cape patches this security hole by allowing you to automatically rotate your IMSI every 24 hours. In practice, this means you appear as a different subscriber every day, making it much more difficult for anyone to identify your device or track your movements.

5. Last-Mile Encrypted Texting

Most people receive One-Time Passwords (OTPs) through unencrypted SMS messages, leaving their most sensitive data and accounts vulnerable to a variety of threats.

Cape allows you to route all SMS/MMS messages through the Cape app, ensuring that every message you receive is middle-to-end encrypted. The messages are then securely decrypted within the Cape app, ensuring only you can see and read their contents.

Note: This feature is only available on iPhone. Android coming soon.

6. Secondary Numbers

Are you tired of spam messages from brands, phone call surveys, and scammers trying to trick you into sharing sensitive information over the phone? The reason why most people are exposed to these nuisances is that we are often required to share our phone numbers with retailers, websites, apps, and service providers.

While messages and phone calls can be annoying, what’s worse is that your number can easily become a target for data brokers and bad actors. That’s why many people turn to VoIP numbers as secondary lines. VoIPs are a decent option, but they don’t fully solve the issue—they are not encrypted, you can’t use them for 2FA, and they’re an additional cost each month.

When you sign up for Cape, you get two free additional SMS/MMS lines that are middle-to-end encrypted. This allows you to use Secondary Numbers for online shopping, signing up for services and discounts, and receiving secure OTPs, while your primary phone number is reserved for friends and family.

7. Network Lock

Traditional cellular networks were designed for interoperability, not security. Outdated and legacy network protocols like SS7 have vulnerabilities that allow attackers to hack in and track your location, intercept your calls and texts, and steal sensitive information.

Cape’s Network Lock uses a proprietary signaling proxy to verify that your device’s physical location matches the network it’s trying to attach to. If anything looks suspicious, like a mismatched location, we block the connection.

8. Encrypted Voicemail

Voicemails can reveal more than you think, from personal messages to authentication codes, yet most voicemail systems are outdated and unencrypted.

Cape encrypts your voicemails so that only you can access them.

9. Secure Global Roaming

To access phone service while traveling abroad, your phone typically needs to connect to local telecom providers. The trouble is, there’s no guarantee all networks are secure, and not every government treats privacy the same.

Cape doesn’t leave anything to chance. We let you route traffic through our U.S.-based mobile core, so you can safely use international data roaming without exposing your identity or sharing sensitive data or communications with foreign carriers.

With Cape, you get up to 15 GB per month of international roaming, included in your monthly plan.

Get Started With Cape Today

If you’re ready to make a switch from legacy telcos to America's privacy-first mobile carrier, visit cape.co/get-cape and test out Cape in practice for just $30 for your first month.

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