[October 2026] Mortgage interest rates, minimum 1.195% | maximum 1.747%. I asked 9 banks. We chose SBI Shinsei Bank.

In preparation for purchasing a condo in February, I went around and asked various banks for their “latest partner interest rates” as of October.

To conclude, there was a 0.552% interest rate difference between the lowest and highest banks.

Although I mostly write about investment topics, a mortgage is actually “one of the largest fixed costs in life that you cannot just leave alone.” This time, I will honestly disclose the numbers I was given exactly as they are.

Partner interest rates I heard in October (in ascending order)

Rank Bank Interest Rate 1 MUFG Bank 1.195% 2 Resona Bank 1.25% 3 Mizuho Bank 1.275% 4 SBI Shinsei Bank 1.28% 5 Chiba Bank 1.35% 6 Sony Bank 1.697% 7 Docomo SMTB Net Bank 1.699% 8 Sumitomo Mitsui Trust Bank 1.7% 9 Rakuten Bank 1.747%

※These are the figures I confirmed with sales companies in October 2026. Borrowing conditions (interest rate type, term, group credit life insurance, etc.) may have different premises for each company, so please check the official information from each bank or consult with a representative for the latest and accurate details.

When lined up, they clearly split into five banks in the 1.2% to 1.35% range and four banks around 1.7%.

I tried calculating the difference in numbers

I made a rough estimate of how much of a difference it would make.

The conditions are a simple calculation assuming a loan of 40 million yen, 35 years, equal principal and interest repayment, and the same interest rate for the entire period (actual interest rate types and various fees are not considered).

• Interest rate 1.195%: Monthly approx. 116,600 yen, total interest approx. 8.97 million yen

• Interest rate 1.28%: Monthly approx. 118,200 yen, total interest approx. 9.65 million yen

• Interest rate 1.747%: Monthly approx. 127,400 yen, total interest approx. 13.5 million yen

Comparing 1.195% and 1.747%, the difference in interest alone is about 4.5 million yen. It also differs by about 10,000 yen per month.

I have put 2.4 million yen into my daughter’s Junior NISA and have grown it over time. From that perspective, 4.5 million yen is a fairly large figure for “money that just goes out without doing anything.”

We chose SBI Shinsei Bank

At the time, I decided to purchase three months after changing jobs, and from the beginning, I was recommended Sony Bank by the representative, mainly focusing on internet banks. When I approached MUFG and others after more than a year had passed since changing jobs, unfortunately, it seemed they also looked at my other investment property loans, etc., and although they asked various detailed questions, it was a no-go, so I ultimately chose SBI Shinsei Bank, where the interest rate increase range was more stable than Sony Bank’s.

Interest rate is the most prominent number when choosing a mortgage, but I feel it is important to look at the “total amount,” including administrative fees, group credit life insurance, and repayment flexibility. Another point is that it only cost an additional 0.1% to add cancer insurance.

It is also important to “decide in advance” for mortgages

It was the same with investments, but what helps you when you are lost is the criteria you decided on when you were calm.

• Decide on a maximum monthly repayment amount

• Compare not just interest rates, but the total cost including fees and group credit life insurance

• Ask multiple banks and compare the figures side-by-side

By asking 9 banks and comparing them this time, I was able to see the big picture: that they are divided into the 1.2% range and the 1.7% range. If I had decided based on just one bank, I don’t think I would have had this perspective.

Summary

• The October 2026 partner interest rates range from a minimum of 1.195% (MUFG Bank) to a maximum of 1.747% (Rakuten Bank)

• A simple calculation for 40 million yen over 35 years shows a difference of about 4.5 million yen in total interest

• We decided on SBI Shinsei Bank (1.28%)

• It is important to compare not just interest rates, but the total cost including conditions

I will write honestly about any further progress as we head toward our purchase in February.

At NISA Houchi Papa, I share my experiences with Junior NISA and the behind-the-scenes of my financial decisions. I would be happy if you followed me if you found this helpful.