What interest rate should I use for a Japan mortgage?

Japanese mortgage rates are low by global standards. The popular Flat 35 fixed-rate product sits around 1.8 percent, while variable-rate loans from megabanks are often near 0.5 to 0.7 percent. Use the rate your lender quotes; variable rates can change while fixed Flat 35 rates are locked for the full term.

How much deposit do I need to buy in Japan?

Japanese lenders typically finance 80 to 90 percent of the property value, so a deposit of 10 to 20 percent is common. Some banks lend up to 100 percent to strong borrowers, but a larger deposit lowers your loan-to-value ratio and can secure a better rate. Permanent residency or stable employment usually helps.

How long can a Japanese mortgage run?

Standard terms run up to 35 years, which is the maximum for the Flat 35 product as its name suggests. The loan generally must be repaid by around age 80, so older borrowers may face a shorter maximum term. A longer term lowers the monthly payment but increases total interest paid.

How is the monthly payment calculated?

This tool uses the standard amortising loan formula, the same one Japanese lenders use for the common equal-payment (gankin kintou) repayment method. Each monthly payment is identical and gradually shifts from mostly interest to mostly principal over the life of the loan.

Does this include taxes and fees?

No. This calculator covers only the loan repayment. Buying property in Japan also involves an acquisition tax, registration and licence tax, stamp duty, agent fees, and a loan guarantee fee, which together can add several percent to the purchase. Budget for those separately.

Japan Mortgage Calculator

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Japanese home loans are unusually cheap by international standards, with fixed Flat 35 rates near 1.8 percent and variable megabank rates often under 1 percent. This calculator models a Japanese mortgage using the standard equal monthly payment method, so you can see your repayment, total interest, and loan-to-value position before you apply.

How it works

The tool uses the standard amortising loan formula, where every monthly payment is identical and the split between interest and principal shifts over time:

loan    = price − deposit
i       = annual rate / 12
n       = years × 12
payment = loan × i / (1 − (1 + i)^−n)
LTV     = loan / price × 100

When the interest rate is zero the payment is simply the loan divided by the number of months. The loan-to-value ratio is checked against the typical Japanese ceiling of 80 to 90 percent.

Example and notes

A 50,000,000 yen apartment with a 10,000,000 yen deposit leaves a 40,000,000 yen loan. At 1.8 percent fixed over 35 years that is roughly 128,000 yen per month and about 14 million yen of total interest. Switching to a 0.6 percent variable rate drops the payment to around 106,000 yen but exposes you to future rate rises. Remember to budget separately for acquisition and registration taxes, stamp duty, and the loan guarantee fee, which are not part of the repayment shown here.