35-year vs 40-year vs 50-year mortgage

The core trade-off

Several banks now permit terms up to 50 years, subject to age, property, and underwriting limits — au Jibun Bank states 1–50 years, and Sumishin SBI Net Bank publishes up to 50 years for new borrowing. A longer term lowers the monthly payment, which can make a purchase feel affordable, but it raises total interest substantially, may add a rate surcharge (au Jibun adds 0.10 point beyond 35 years; PayPay Bank’s long-term surcharge rises for later executions), carries age limits (the loan usually must be repaid before a set age such as 80), and slows how fast you build equity.

How to decide

Use a longer term for genuine affordability and cash-flow flexibility, not to stretch into a more expensive home than you can really afford. The extra decades of interest are a real cost, and a mortgage that extends materially beyond your expected working income is a warning sign. If you can comfortably afford a 35-year payment, that usually minimizes total interest; choose 40 or 50 years deliberately, understanding the surcharge and the slower equity build, and consider prepaying later if your income allows.

Key points to carry away: A longer term lowers the monthly payment but raises total interest; Terms beyond 35 years may carry a rate surcharge (e.g. au Jibun +0.10 point); Age limits apply — the loan usually must end before a set age (e.g. 80); A longer term slows equity accumulation. 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.