How to get home internet in Japan: fiber, 5G home routers, and the traps

Quick conclusion

For a stable long-term connection, fiber (hikari, 光回線) at roughly 4,000-6,000 yen per month is the default choice in Japan - but it takes two to four weeks or more to install, so apply early and bridge the gap with a rental router if needed. If you cannot get landlord permission, your building cannot be wired, or you move often, a home 5G router (around 4,500-5,500 yen, no construction) is the practical alternative.

This article contains affiliate-related comparisons; the conditions below matter regardless of provider.

Your three realistic options

Getting fiber, step by step

1. Check the building first. Ask the management company or landlord whether the building is wired (配線方式 also affects your speed). If your room has an optical outlet, installation may need no visit at all. 2. Choose a provider. Most consumer fiber is NTT infrastructure resold under different brands ("hikari collaboration"), so compare price, campaign conditions, contract period, and support language rather than physics. Some providers offer English support - the service notes on this page are a starting point. 3. Book the construction visit. You (or someone) must be home. Slots fill up fast in February-April. 4. Construction and activation. The initial construction fee is commonly 15,000-40,000 yen; campaigns often waive it in installments that are forgiven only if you stay the full period. 5. Set up your own router. The line terminal (ONU) is provided; the Wi-Fi router is often a paid monthly rental. Buying your own router typically pays for itself within a year.

The four contract traps to read before signing

• Auto-renewing contract periods. Two-year terms with a narrow no-fee cancellation window remain common. Note the window in your calendar the day you sign.
• Campaign cashback conditions. High cashback often requires applying through a specific page, staying enrolled in options, and claiming the money in a specific month a year later. Screenshot the conditions.
• The price after year one. Many advertised prices are first-year discounts. Compare the ongoing price, not the promotional one.
• Construction fee installments. "Free construction" is often a 24-36 month installment that becomes due in full if you cancel early - a serious cost if you might move. If you move within Japan, some providers transfer the line for a smaller fee; see moving with internet and phone contracts.

If fiber is not possible in your building

Older buildings sometimes cannot be wired, and some landlords refuse drilling. In that case a home 5G router is the answer: no construction, no landlord, working the day it arrives. Check the signal at your address on the carrier's coverage map before contracting, confirm any fair-use throttling rules, and prefer plans with no or short minimum periods so you can switch if the speed disappoints.

While you wait

Fiber's multi-week lead time is the most common surprise. Order a rental pocket Wi-Fi for the gap, or lean on your phone's tethering if your SIM plan allows it - if you are still choosing that plan, start with how to choose a SIM card.