How loans work in Japan

Principal, interest, and term

Principal (元金) is the amount borrowed before interest and fees. Interest (利息) is the price of using that money, charged at a nominal annual rate on the outstanding balance — not on the original principal forever. The loan term (借入期間) is the repayment period: a longer term lowers each monthly payment but usually increases total interest and can carry a rate surcharge. Several banks now permit terms up to 50 years, subject to age, property, and underwriting limits.

Repayment, collateral, and default

Amortization (返済予定) is how each payment splits between interest and principal. Secured loans pledge collateral (担保): a mortgage lender registers a first-ranking mortgage over the property, which is why secured loans carry lower rates and longer terms than unsecured card or consumer loans. If you default, late-payment charges (遅延損害金) accrue, but the more serious consequences are credit-record damage, acceleration of the whole balance, guarantee-company performance, collection, and ultimately foreclosure — and surrendering the property does not necessarily erase any remaining deficiency.

Key points to carry away: Interest is charged on the outstanding balance, so early payments on a level-payment loan are mostly interest; A longer term lowers the monthly payment but usually raises total interest; Collateral (a registered mortgage) secures a loan; default can lead to enforcement and sale; Surrendering collateral does not always erase a remaining deficiency. Use the linked guides and calculators for the full decision, and confirm anything material with the lender, a licensed broker, a judicial scrivener, or a tax accountant before you act.