Debt-service ratios, qualifying income, and household affordability versus the bank maximum.
The debt-service ratio is annual scheduled repayments ÷ qualifying income; Flat 35 generally allows up to 30% below ¥4 million income and 35% at or above it, but the lender’s maximum is not a prudent household target.
The debt-service ratio (返済負担率) is usually annual scheduled repayments divided by qualifying annual income, and it counts all your debts — the new mortgage plus car loans, card-loan minimums, and other obligations. Flat 35’s published framework generally allows total annual debt repayments of no more than 30% for income below ¥4 million and 35% for income of ¥4 million or more. Qualifying income for the self-employed or variable earners is often a normalized, lower figure, and existing debts directly reduce the mortgage you can be approved for.
A lender’s maximum is not a household recommendation. The published ratio is an underwriting ceiling; a prudent household usually targets a lower ratio after accounting for income tax, resident tax, national pension, national health insurance, childcare, ongoing maintenance, and the possibility of rate increases on a variable loan. Borrowing the maximum approved leaves no margin for a rate rise or a life change, so decide affordability on your own stressed budget, not on the bank’s ceiling.
Key points to carry away: Debt-service ratio = annual scheduled repayments ÷ qualifying annual income; Flat 35: generally ≤30% for income below ¥4 million, ≤35% at ¥4 million or more; The ratio counts all debts, not just the mortgage — car loans and card limits reduce your headroom; A lower ratio is safer after tax, childcare, pension, maintenance, and rate increases. 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.
Fixed-rate mortgage · Japan Housing Finance Agency
A long-term fixed-rate mortgage program backed by the Japan Housing Finance Agency, offered via partner lenders and often accessible without permanent residency.
Fees: Rate and fees vary by lender and loan-to-value — verify current terms.
Annual scheduled debt repayments divided by qualifying annual income; it counts all your debts, not just the mortgage.
Commonly 30% of income below ¥4 million and 35% at ¥4 million or more.
Usually not; approval is an underwriting ceiling, not a household financial recommendation.