Updated: 2026-09-15 16:18:54
If your stay in Japan is settled at six months — an exchange semester, a half-year posting, a research placement with a fixed end date — the question is no longer which type of connection to get. It's how to buy it without leaving money on the table.
The obvious move is to take the 6-month contract, because the monthly rate is lower than the 3-month rate. That instinct is right, but for a narrower reason than most people assume, and it comes with one condition worth understanding before you order. This article works through the actual comparison, including the case where the 6-month plan is the more expensive choice.
Everything below describes CDJapan Rental's own contract terms and rates. Monthly pocket WiFi in Japan isn't sold on a common set of rules, so the arithmetic here is a worked example built on our numbers rather than a description of the market.
Not yet sure whether pocket WiFi, a SIM, or a domestic carrier is right for your situation? Start with our complete guide to internet in Japan for 3–12 month stays, then come back here.
First, a correction to a common assumption. With CDJapan Rental, covering six months on a 3-month plan does not mean buying two 3-month plans. When the minimum term ends, our contract doesn't stop — it continues month to month at the same rate until you cancel. You don't re-order, you don't return the router and wait for a new one, and there's no gap in service.
So the real comparison isn't "one long contract versus two short ones with admin in between." It's simpler than that: six months billed at the 3-month monthly rate, or six months billed at the 6-month monthly rate. Same device, same unlimited data, same service. The only variable is the rate.
Across the full six months, the lower rate saves you roughly half a month's rent. That's the whole difference — real money, but not the dramatic gap the plan tiers might suggest at a glance. Being straight about the size of it matters, because the number changes what question you should actually be asking.
The question isn't "which plan is cheaper?" It's "how confident am I that I'll finish six months?" Once the saving is modest, your exit risk dominates the decision.
Both of our plans charge an early-termination fee of roughly one month's rent if you cancel inside the minimum term. On the 3-month plan that fee stops being a factor after month three. On the 6-month plan it hangs over you until month six.
Run the totals for every possible exit point:
| If you actually leave at the end of | Cheaper choice in hindsight | Why |
|---|---|---|
| Month 3 | 3-month plan | Minimum term complete, no fee; the 6-month plan pays a fee on top |
| Month 4 | 3-month plan | Rolling month to month with no fee beats the lower rate plus a fee |
| Month 5 | 3-month plan | Same — the fee more than cancels out five months of rate saving |
| Month 6 (full term) | 6-month plan | No fee, and the lower rate applies to all six months |
There is no partial win. The 6-month plan pays off if and only if you see it through. Leave at any earlier point and the 3-month plan rolling month to month would have cost you less. That result comes out of two of our own numbers: the gap between our rate tiers, and an early-exit fee of about one month's rent.
That gives you a decision rule that doesn't need a spreadsheet: if your end date is genuinely fixed — a semester with an official end, a contract with a return flight already booked — take the 6-month plan and collect the saving. If there's a realistic chance you'll leave early, take the 3-month plan, let it roll, and treat the slightly higher monthly rate as the price of an exit option.
Extending is the easy direction. With CDJapan Rental, once the minimum term ends the contract continues month to month at the same rate with the same router. Nothing to re-order, no new device, no gap in coverage, no re-verification of your details. You cancel whenever you're actually done, with no fee at that point.
One thing not to do: cancel a plan and immediately re-order a fresh one to reset onto a new introductory month. You'd have to return the hardware, wait for a new shipment, and go offline in between — and the cancellation and return deadlines don't line up neatly enough to make that worth attempting. If you already suspect at the ordering stage that you'll be in Japan closer to a year, look at the 12-month rate instead, which is lower again. Our working holiday internet guide covers the full-year case in detail.
Exchange students are the single most common six-month profile, and Japan's academic year has a shape worth planning around. Japanese universities run two main intakes: April, with the spring semester running to roughly the end of July; and September or October, with the autumn semester running to roughly early February. A single-semester exchange in either intake lands almost exactly on a six-month window, with a little room at each end for orientation and moving out.
Three practical points follow from that:
If you're comparing this against relying on campus WiFi, our guide to internet options for studying abroad in Japan covers where university networks fall short.
With CDJapan Rental, cancellation is submitted through My Page and the deadline is 3:00 p.m. Japan time on the 20th of the month.
| When you submit | Contract ends | Next month's charge |
|---|---|---|
| Before 3:00 p.m. JST on the 20th | End of that same month | Not charged |
| After 3:00 p.m. JST on the 20th | End of the following month | Charged |
Returning the device is not a cancellation.
If you post the router back without submitting a cancellation request through My Page, billing continues. Your card keeps being charged on the 1st of each month for a device already back in the warehouse. Submit the cancellation first, then return everything that was shipped to you — router, AC adapter and charging cable.
These deadlines and the My Page process are CDJapan Rental's own rules. Return logistics are covered on the pickup and return page.
Both unlimited plans cost the same at every contract length, and both are genuinely unlimited with no monthly data cap, so price and data allowance can't decide this. The difference is hardware and network only.
| SoftBank Unlimited | WiMAX+5G Unlimited | |
|---|---|---|
| Device | FS030W | Speed Wi-Fi 5G X11 |
| Weight | 128 g | 174 g |
| Network | SoftBank 4G LTE | 5G (Sub6/NR) / 4G LTE / WiMAX 2+ |
| Max downlink | 150 Mbps | 2.7 Gbps |
| Simultaneous devices | Up to 5 | Up to 16 |
| Battery | About 490 minutes | About 490 minutes (4,000 mAh) |
Quoted speeds are theoretical maximums under best-effort terms and vary with location, time of day and network congestion. Japan's 5G footprint is still concentrated in urban areas, so a WiMAX+5G device falls back to 4G LTE across much of the country.
Six months is long enough that ergonomics start to matter more than specs. If you'll be carrying the router in a bag every day between a dorm and a campus, the lighter SoftBank device is noticeably easier to live with. If it's going to sit in shared accommodation serving a laptop, a phone, a tablet and a housemate or two, the higher connection count on WiMAX+5G is the deciding factor. There's also a SoftBank 100GB plan on the same hardware as the SoftBank unlimited plan, for lighter users who want a lower monthly cost.
Worth restating for anyone arriving on a student or business visa, since the constraints that rule out Japanese domestic carriers don't apply here. CDJapan Rental's monthly plans require no residence card and set no minimum visa validity; payment accepts foreign-issued Visa, Mastercard, JCB and AMEX, so the order can be completed from home before you fly; and the device ships to an airport post office, a hotel or an Airbnb address, so you're online on arrival day rather than after a bank account and a two-week activation wait.
Orders are accepted up to 3:00 p.m. Japan time three days before your rental start date, though ordering about a week out is safer for stock and delivery reasons.
| Minimum term | Monthly rate (both unlimited plans) | Best for |
|---|---|---|
| 3 months | ¥6,600 / month | Uncertain end date, exit flexibility |
| 6 months | ¥6,000 / month | Fixed half-year stays, single-semester exchange |
| 12 months | ¥5,500 / month | Working holiday, full academic year |
Reference: CDJapan Rental published monthly rates for WiMAX+5G Unlimited and SoftBank Unlimited. Both plans are identically priced at every term length. Check the WiMAX+5G and SoftBank product pages for current rates and the first-month discount.
| Charge | Amount | When it applies |
|---|---|---|
| Late return | ¥1,200 per day | Device not received after your contract ends |
| Loss or damage | ¥24,000 per device | Also applied if the device isn't received within 5 days of contract end |
With CDJapan Rental, only if you complete the full six months. Both of our plans charge an early-termination fee of about one month's rent inside the minimum term, and on the 6-month plan that exposure runs all the way to month six. If you leave at the end of month three, four or five, the 3-month plan rolling month to month would have cost less. These figures are CDJapan Rental's own.
The rate tiers are set by the contract you order, so choose the term that matches your plans at the ordering stage. If you're unsure, contact CDJapan Rental before ordering rather than after — once a contract is running, cancelling and re-ordering means returning the hardware and going offline in between.
With CDJapan Rental, nothing to do. The contract continues month to month at the same rate with the same device once the minimum term ends, and you can cancel at any point after that with no fee. If you already expect to stay closer to a year, the 12-month rate is lower again and worth ordering from the start.
No to both. There's no residence card requirement and no minimum visa validity, and foreign-issued Visa, Mastercard, JCB and AMEX cards are accepted for the monthly charge. See our guide to getting internet without a Japanese bank account for how this fits with settling in.
Yes. WiMAX+5G supports up to 16 simultaneous connections and SoftBank up to 5, so both handle multi-person households, with WiMAX+5G giving more headroom for shared accommodation.
With CDJapan Rental, everything that was shipped to you: the router, the AC adapter and the charging cable. Missing accessories are treated as loss or damage, and a device not received within five days of your contract ending is also treated as a loss.
Six months in Japan, settled before you land.
CDJapan Rental's 6-month unlimited pocket WiFi needs no residence card, no Japanese bank account, and no two-year lock-in — order from home, collect it at the airport, and get the lower monthly rate for the whole stay.
For use over 90 days (Monthly Plan)
