Internet Cost Japan is a free, English-language tool and guide for foreign residents trying to figure out what home internet they can actually get — 光回線 (fiber), a ホームルーター (home router), or a 格安SIM (budget SIM) — and what it truly costs over two years, without the campaign math designed to obscure it.
How we source our numbers
Provider base fees (月額料金), standard construction fees (工事費), and cancellation fees (違約金) are drawn from each provider's own 2026 pages or multiple corroborating sources, recorded with dated source comments in our data files. All figures are list / tax-included (税込) prices.
Why we exclude campaign cashback
We deliberately do not fold advertised キャッシュバック (cashback) into the totals. Campaigns change every month, often pay out 6–12 months later, and are forfeited if you miss a claim window — so building them into a "true cost" would be false precision. Our totals use base fees plus the standard construction fee amortized over 24 months; treat any cashback that actually lands as a bonus.
Independence
This is an independent project, not affiliated with any internet or mobile provider or with any government body. It is informational only and not financial advice. Always confirm current terms directly with a provider before signing.
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