What Is Rakuten eSIM? A Complete A-to-Z Guide

Rakuten eSIM is a digital SIM provided by Rakuten Mobile, allowing users to connect to mobile networks in Japan without a physical SIM card. With a fully online activation process, Rakuten eSIM offers flexibility, easy management, and cost optimization for users in Japan. However, not everyone clearly understands what Rakuten eSIM is or when it is the right choice. This article will analyze it in detail, from the concept and pros and cons to the target users, so you can make the right choice. Read the full article to avoid confusion when choosing an eSIM in Japan.

1. What is Rakuten eSIM?

Rakuten eSIM is a digital SIM (embedded SIM) issued by Rakuten Mobile and built into the hardware of a phone or mobile device. Instead of inserting a physical SIM card, users only need to download the eSIM profile to their device via QR code or activate it directly in the Rakuten Mobile app.

This eSIM works like a traditional SIM: it allows users to sign up for a plan, connect to mobile networks, make calls, send messages, and access the Internet. The difference is that all SIM management is done through software, with no manual insertion or removal required.

Rakuten eSIM is used to connect to 4G/5G mobile networks in Japan, serving needs such as Internet access, calling, and receiving SMS (with plans that include a phone number). In practice, many users choose Rakuten eSIM to use alongside another SIM, most commonly keeping their Vietnamese SIM to receive OTPs while using Rakuten eSIM for data and local communication in Japan.

2. Pros and cons of Rakuten eSIM

Now that you understand what Rakuten eSIM is, this section will go deeper into its pros and cons so you can assess whether Rakuten eSIM is truly suitable for your needs in Japan, especially for long-term travel, studying, working, or living there.

2.1. Advantages of Rakuten eSIM

Rakuten eSIM is not only a domestic Japanese eSIM but also stands out for its convenience, reasonable cost, and long-term usability. Compared with physical SIM cards or travel eSIMs, the advantages of Rakuten eSIM become very clear in real-world use.

1. No physical SIM required – reduced usage risks

Rakuten eSIM operates entirely as a digital SIM, built into the device. Users do not need to insert or remove a physical SIM card, thereby avoiding common risks such as losing the SIM, breaking the SIM tray, or dust affecting the SIM slot. This is a clear advantage for people who frequently switch devices or use multiple SIMs at once.

2. Quick activation via QR code or app – no need to visit a store

The entire Rakuten eSIM setup process is done online via QR code or directly in the Rakuten Mobile app. Users only need to connect to WiFi, scan the code, and follow the instructions to start using it right away. This saves time and is especially useful for newcomers to Japan or those not comfortable with Japanese when handling store procedures.

3. Rakuten network plus KDDI (au) roaming – reliable coverage

A major strength of Rakuten eSIM is its ability to use the Rakuten network together with roaming on KDDI (au) infrastructure. As a result, even in areas not fully covered by Rakuten, the device can still connect stably through the partner network. This helps reduce signal loss when moving between different areas.

4. Easy plan management in the Rakuten Mobile app

The Rakuten Mobile app allows users to track data usage, real-time charges, and change plans when needed. Centralized management on one platform helps users control costs better, especially for long-term users or those using eSIM as their primary SIM.

5. Diverse plans – flexible according to your needs

Rakuten offers both data-only plans and plans with a Japanese phone number. This allows users to choose the most suitable option:

• Data-only plans for Internet access and short-term travel.
• Plans with a Japanese phone number are suitable for daily life, service registrations, SMS verification, and local communication.

6. Low cost in Japan – a clear competitive advantage

Compared with major carriers such as SoftBank, NTT Docomo and au, Rakuten Mobile is known for more accessible pricing. This is why many long-term users in Japan choose Rakuten eSIM to save on monthly costs.

7. Japanese local phone number – convenient for daily life and procedures

With plans that support a Japanese phone number, Rakuten eSIM allows users to receive verification SMS, register bank accounts, food delivery apps, administrative services, or handle everyday communication. This is an important difference from many travel eSIMs that only support data.

8. Supports 4G/5G – stable speeds in major cities

Rakuten eSIM supports both 4G and 5G, delivering stable access speeds in major cities such as Tokyo, Osaka, and Nagoya, where Rakuten has invested heavily in infrastructure. This meets common needs such as online work, remote learning, video streaming, and video calls.

2.2. Disadvantages of Rakuten eSIM

Alongside its cost advantages and long-term usability in Japan, Rakuten eSIM still has some limitations that users should carefully consider before choosing it. These disadvantages especially affect short-term travelers or those who need flexible use across multiple countries.

• Uneven coverage: In suburban, rural, or mountainous areas, Rakuten eSIM often has to roam on au, which can mean slower speeds and less stability than direct coverage from Rakuten Mobile.
• Complicated registration process: Some plans require a residence address and documents in Japan, which is not suitable for short-term travelers.
• Less flexible for short-term travel: Verification and activation take time, so it is not as instantly usable as a travel eSIM.
• Limited international roaming: Mainly used within Japan, so it is not suitable for people traveling across multiple countries.
• Device compatibility limitations: It only works reliably on devices that support eSIM and are compatible with Japanese bands; some imported phones may experience signal issues or fail to activate.

3. Who is Rakuten eSIM suitable for?

Not everyone should use Rakuten eSIM. In practice, this type of eSIM works best when used by the right users and in the right context. Below are the groups most suitable for Rakuten eSIM, based on length of stay and practical needs in Japan.

• Long-term residents in Japan: Rakuten eSIM is suitable for long-term residents thanks to its low cost, stable local plans, and a Japanese phone number for everyday use. It is a more economical choice than many major carriers when used over a long period.
• Students, workers, and trainees: This group often needs to receive verification SMS, local calls, and register for services in Japan such as banking, housing, and payment apps. Rakuten eSIM meets these needs well thanks to support for a Japanese phone number and convenient management in the Rakuten Mobile.
• Short- to mid-term workers in Japan: For people working in Japan for a few months to under a year who have time to prepare in advance, Rakuten eSIM is a more reasonable solution than a travel eSIM. Local plans provide stable usage and lower costs than short-term plans.
• People who want to keep their Vietnamese SIM alongside it: Rakuten eSIM can be used for Internet and communication in Japan, while the Vietnamese SIM is kept for receiving OTPs, bank calls, or domestic services. This parallel-use approach is especially suitable for people who need to maintain two-way Vietnam – Japan contact.

4. When should / shouldn’t you use Rakuten eSIM?

Choosing the right time to use Rakuten eSIM will help you avoid wasted costs and reduce unnecessary inconvenience. Below is a quick comparison table to help you determine whether Rakuten eSIM is suitable for your situation.

Use Rakuten eSIM if:

• You are in Japan long-term for study, work, or living.
• You need a Japanese local phone number for communication and service registration.
• You prioritize low cost, and mainly use it in major cities.
• You have time to register and are ready to complete the required verification steps.
• You want to use a stable domestic eSIM from Rakuten Mobile instead of a travel eSIM.

Do not use Rakuten eSIM if:

• You are only traveling for a short period (about 5-14 days).
• You frequently travel to remote or rural areas.
• You need a buy – set up – use immediately solution without document verification.
• You need to travel to multiple countries in the same trip.

In these cases, users usually prefer Japan eSIM for travel, since it can be purchased in advance, set up quickly, and used immediately upon arrival, instead of having to go through a local registration process like Rakuten eSIM.

5. Quick comparison: Rakuten eSIM vs Japan travel eSIM

This is the section that helps many people make a quick decision, because Rakuten eSIM and Japan travel eSIM are often confused. The comparison table below clearly shows the key differences between the two options.

This distinction is similar when comparing domestic eSIMs and travel eSIMs at major transit points in the region, such as eSIM Singapore, where short-term users often prioritize speed and convenience over registering with a local carrier.

6. FAQs – Frequently asked questions about Rakuten eSIM

When learning what Rakuten eSIM is, users often have questions about switching, installation, and real-world usage. The FAQs below compile the most common questions for quick reference.

Question 1: How do I switch a Rakuten SIM to eSIM?

Users log in to their Rakuten Mobile account, choose to switch from a physical SIM to eSIM, and complete the required verification steps. After that, the system will issue a new eSIM profile and the old physical SIM will be deactivated.

Question 2: Where can I get the Rakuten eSIM QR code?

The Rakuten eSIM QR code is displayed directly in the Rakuten Mobile account or sent by email after successful registration. Users only need to scan this code to install the eSIM on their device.

Question 3: Can Rakuten eSIM be used alongside a Vietnamese SIM?

Yes. If your device supports eSIM and a physical SIM, you can keep your Vietnamese SIM for receiving OTPs and use Rakuten eSIM for Internet and calls in Japan.

Question 4: Is Rakuten eSIM suitable for short-term travel?

It is not the best choice. For short trips, a Japan travel eSIM is usually more convenient because it does not require verification and can be used immediately after purchase.

If you are still wondering whether to choose Rakuten eSIM or a Japan travel eSIM, SimPM is a trustworthy solution to get started. At SimPM, you receive advice on the right eSIM plan based on your length of stay, device, and actual needs, along with technical support throughout the installation and usage process. SimPM offers many popular travel eSIM options in the region such as Thailand eSIM, eSIM Malaysia, eSIM Singapore, China eSIM hay eSIM Philippines,… meeting diverse needs from travel and business trips to multi-country trips.

Rakuten eSIM is a cost-effective digital SIM solution, suitable for long-term residents in Japan or those who need a local phone number. Although it still has some limitations in terms of procedures and coverage in remote areas, Rakuten eSIM remains a worthwhile option if you prioritize cost and flexible management. Understanding what Rakuten eSIM is and when to use it will help you make the right choice from the start and avoid problems later.