The three official tiers
Rakuten Saikyo Plan is 1,078 yen per month up to 3GB, 2,178 yen over 3GB to 20GB, and 3,278 yen over 20GB. These prices include tax and exclude calls outside covered conditions or paid options.
You do not choose a data tier in advance. Your actual usage each month determines which tier you fall into. If you use less data, you pay less; if you use a lot, the data charge has a clear ceiling at 3,278 yen.
This automatic tier system is one of Rakuten Mobile's most practical features. On months when you mostly use Wi-Fi, your bill drops automatically. On months when you travel or stream heavily, you have a predictable maximum charge.
Rakuten Mobile: Unlimited data ¥3,278/mo or under 3GB ¥1,078/mo (tax incl.).
Who fits the 1,078 yen tier?
If you mostly use Wi-Fi at home and work, and you only use mobile data for maps, messaging, and short browsing sessions outside, 3GB may be enough. Light users who commute on known routes with stable Wi-Fi coverage often find 3GB sufficient.
Students living in dormitories, workers with office Wi-Fi all day, or people who primarily use mobile data for navigation during the weekend may comfortably stay in this tier most months.
However, be aware that a single day of streaming video or working from a café without Wi-Fi can quickly push you past 3GB. If you often have irregular mobile usage days, the 20GB tier is more predictable.
Who fits the 2,178 yen tier?
The 3GB to 20GB range covers most moderate users. If you watch video on commutes, use maps and translation apps frequently, attend video calls from mobile, or use your phone as a hotspot occasionally, this tier is realistic.
For many foreign residents working or studying in Japan, this tier is the most common landing point. It provides enough data for a connected daily life without reaching the maximum charge.
At 2,178 yen, this is still far below what most major Japanese carriers charge for equivalent usage. Compare your current bill and calculate your annual savings before deciding whether to switch.
Who fits the 3,278 yen tier?
Heavy users who stream music and video, download large files, use mobile hotspot regularly, or work remotely from cafés may reach or exceed 20GB. At 3,278 yen, this is still a capped maximum, which means you will never be surprised by an unexpected bill regardless of how much data you use.
Compare the plan with your current bill. If you are paying 5,000 to 8,000 yen per month now and are a heavy user, the annual difference between your current carrier and Rakuten Mobile at the 3,278 yen ceiling can still be very large.
Calls and Rakuten Link
Domestic calls made through the Rakuten Link app do not incur standard per-minute call charges. This is an important feature that is easy to overlook. Install the Rakuten Link app after activating your plan and use it as your default calling app for everyday calls.
Some special numbers, such as 0120 toll-free lines, 110, 119, and certain business numbers, may not work through Rakuten Link or may cost extra. Understand these exceptions before relying entirely on Rakuten Link for all calls.
What else to check before signing up
The official page notes that speed may be controlled during congestion or to provide fair service. A low price does not mean identical quality everywhere. Check the service area map for your home neighborhood, your workplace building, and your main commute route.
Check device support. Not all phones are compatible with every Rakuten Mobile frequency band. If you are using an older or overseas-purchased phone, check the official device compatibility list before signing up.
Also verify your identity document is current. Foreign nationals need a valid residence card or special permanent resident certificate. If your period of stay ends within the next few months, renew before applying for a new phone plan.