Why Is Rakuten Mobile So Ridiculously Cheap?

Short answer: Rakuten Mobile was built from scratch using software instead of expensive proprietary hardware — a completely different technical philosophy from Japan's legacy carriers. That architectural gap translates directly into lower costs, and those savings get passed straight on to subscribers.

The Main Reasons

1. Fully Virtualized, Cloud-Native Mobile Network

Japan's traditional carriers — docomo, au, SoftBank — buy expensive, proprietary hardware for every new generation of network technology. Each upgrade cycle means new physical equipment, installation costs, and ongoing maintenance. That's an enormous bill, and guess who foots it.

Rakuten Mobile went in a totally different direction: swap out proprietary hardware for commodity servers running network functions as software. This is what's called a "cloud-native" or "Open RAN" architecture.

Why does this matter?

A new generation of wireless tech (say, 5G improvements or eventually 6G) can roll out via software update instead of ripping out and replacing hardware
Commodity servers cost a fraction of what specialist telecom equipment does
You can run network operations with a leaner team of engineers

Analogy for non-technical readers: Think of it like streaming music. Old-school carriers were buying CDs — one piece of hardware per function. Rakuten built a streaming service instead — one flexible platform that can handle anything with a software update.

2. KDDI/au Roaming Agreement (through September 30, 2026)

While Rakuten was busy building out its own towers, it struck a roaming deal with KDDI/au — Japan's second-largest carrier. That agreement lets Rakuten Mobile subscribers hop onto the au network (including the coveted 800 MHz "Platinum Band," which punches through walls and covers rural areas well) wherever Rakuten's own infrastructure isn't fully in place yet.

The upshot: Rakuten could offer nationwide service without needing to build out everything from day one — growing fast while keeping capital spending in check.

Note: The au roaming agreement wraps up on September 30, 2026. After that cutoff, Rakuten Mobile runs entirely on its own network. The company has been pushing hard to get new base stations up before that deadline hits.

3. The Rakuten Ecosystem Strategy

Rakuten Mobile CEO Hiroshi Mikitani has said publicly that "Rakuten Mobile is becoming a booster for the growth of the Rakuten ecosystem." The logic is pretty simple when you lay it out:

Mobile is a loss leader for ecosystem growth: Even with thin margins on the mobile plan itself, every new Rakuten Mobile subscriber is a potential Rakuten Ichiba shopper, Rakuten Card holder, Rakuten Bank customer, and so on
Cross-service revenue picks up the slack: The group earns more from subscribers using Rakuten's other services than it "gives up" by keeping mobile pricing low
Subscriber data is genuinely valuable: Having a unified picture of someone's telecom, shopping, and financial behavior is a goldmine for targeted services

Summary: Rakuten Mobile Pricing

Data unlimited after 20 GB
Free domestic calls (via Rakuten Link app)
Maximum ¥3,278/month (tax included)
Family discounts and age-based discounts available
No contract setup fees, no cancellation fees, no minimum term