Fixed or Variable? How to Pick a Mortgage Rate as the Gap Hits a Record High
"Fixed or variable?" is a question almost every buyer pauses over when taking out a mortgage in Japan. In September 2026, reports put the 10-year fixed rate at major banks at 3.84% and the Flat 35 program's rate at 3.46%, both at their highest levels since the program's current framework began, while the variable rate stayed at 1.082% — leaving a gap of 2.21 percentage points, reportedly the widest on record.
This widening gap traces back to the Bank of Japan's gradual rate hikes through 2026. With rate news arriving in fragments, it can be hard to tell what any of it means for your own decision. This article organizes the general points worth comparing before you buy. For your specific loan terms, please confirm with a financial institution or a qualified professional.
What's the actual difference between fixed and variable rates?
A fixed-rate mortgage locks in the interest rate for the loan term (or, for a full-term fixed product, until payoff). Flat 35 is the best-known example, offered through a framework connecting the Japan Housing Finance Agency with private lenders. Because the payment stays the same, it's generally described as easier to plan around over the long term.
A variable-rate mortgage adjusts periodically based on market rate movements. The initial rate is typically lower than a fixed rate, but future payments can change depending on how rates move. Most products include rules meant to soften sudden jumps in payments (such as five-year and 125% caps), though the details vary by lender and are worth checking in the contract.
Why has the fixed rate climbed this far?
As of September 2026, the 10-year fixed rate at major banks (3.84%) and the Flat 35 rate (3.46%) have reportedly reached their highest levels under the program's current framework, in place since October 2017. Fixed rates tend to track long-term rates, such as 10-year government bond yields, and the increase is attributed to how the Bank of Japan's policy stance and inflation outlook have fed through to those longer-term rates.
Variable rates, by contrast, tend to move more closely with the short-term policy rate, and have stayed relatively low at 1.082%. The result is a gap of 2.21 points, reportedly the widest recorded — meaning the choice between the two now carries a bigger difference in total repayment over time, which is one reason comparison matters more in this environment.
With the gap this wide, what should you actually compare?
Looking only at the headline rate makes variable look like the better deal, but in practice it needs to be weighed against uncertainty over how much and how soon rates might rise. A fixed rate offers the reassurance of a locked-in future payment, at the cost of a higher starting rate.
When comparing, it's worth looking at total cost — including guarantee fees, administrative fees, and the coverage terms of group credit life insurance — rather than just the monthly payment. Some products sit between the two, such as an initial fixed-rate period (e.g., fixed for the first 10 years), so running simulations across several lenders is generally recommended.
What should overseas buyers of Japanese property keep in mind?
For someone living overseas or a non-Japanese national applying for a mortgage from a Japanese lender, permanent residency status and a track record of income earned in Japan are commonly part of the screening criteria. If those conditions aren't met, an all-cash purchase or financing arranged through a lender in one's home country are sometimes considered instead.
Buying in cash sidesteps the direct effect of the rate gap, but Japan's overall interest-rate environment remains one factor that can influence the yen and the broader property market — worth keeping in mind when thinking about timing and area selection.
Mortgage rate figures as of September 2026
- 10-year fixed rate (major banks)
- 3.84%
- Flat 35
- 3.46%
- Variable rate
- 1.082%
- Fixed-variable gap
- 2.21points
Highest under the current framework
Highest since October 2017
Remains relatively low
Reportedly a record
Related frameworks and laws
- Japan Housing Finance Agency Act
- The legal basis for Flat 35, a full-term fixed-rate mortgage program offered jointly by the Agency and private lenders.
- Interest Rate Restriction Act, Article 1
- Sets general ceilings for interest rates on loan agreements. Most mortgages are said to operate within these limits, though the specifics should be confirmed individually.
- Building Lots and Buildings Transaction Business Act, Article 35
- Requires a licensed real estate broker, when arranging financing for the purchase price, to explain its terms and what happens if the financing falls through, as part of the mandatory pre-contract disclosure.
General points of comparison between fixed and variable rates (general guidance only)
| Point of comparison | Fixed rate | Variable rate |
|---|---|---|
| Starting rate level | Tends to be relatively higher | Tends to be relatively lower |
| Future payments | Tends to be locked in from the start | Can change with rate movements |
| Often described as suiting | Buyers who prioritize long-term planning certainty | Buyers who want a lower initial payment |
| Worth confirming | The fixed period and terms through payoff | Review timing and whether a payment cap applies |
Common misreadings and how to avoid them
✕Assuming the variable rate is always the better deal just because today's number is lower.
→Run total-repayment simulations across a few rate scenarios before comparing, factoring in the uncertainty of future rate moves.
✕Focusing only on the headline rate without checking guarantee fees, administrative fees, or life insurance coverage terms.
→List out the total cost, including all fees, for each lender before deciding.
✕Signing a variable-rate contract without confirming whether the lender applies a five-year rule, a 125% cap, or neither.
→Get the review terms in writing before signing, and ask the loan officer about anything unclear.
✕Choosing a property before confirming whether you'll actually qualify for a mortgage as an overseas resident.
→Confirm financing prospects with a lender first, then move forward with the property search.
Before comparing fixed vs. variable
- Got simulations for both fixed and variable rates from more than one lender
- Checked guarantee fees, administrative fees, and group credit life insurance terms alongside the rate
- For a variable rate, confirmed the review timing and whether a payment cap applies, in the contract
- Checked whether a hybrid product, such as an initial fixed-rate period, is available
- Organized your own repayment plan, including term length and any planned early repayments
- If living overseas or a non-Japanese national, confirmed the lender's screening requirements in advance
Frequently asked questions
- Q. Which is actually better, fixed or variable?
- A. No one can say for certain how rates will move, so there's no universal answer. It generally comes down to whether you value predictable future payments or a lower starting payment more.
- Q. With the gap this wide, is now the time to switch to fixed?
- A. The size of the gap is one factor, but not the only one. It's worth thinking through your own financial plan and risk tolerance, and discussing it with a lender or professional, before deciding.
- Q. Can I get a Japanese mortgage while living overseas?
- A. Requirements vary by lender, but permanent residency status and a track record of income in Japan are commonly required. Where that isn't possible, an all-cash purchase or financing from a lender in your home country are sometimes used instead.
In the SUMIMOTO Hub app, a 24-hour AI advisor explains the general thinking behind fixed and variable mortgage rates and Japan's housing loan programs in multiple languages. For your specific rate plan or eligibility, please confirm with a financial institution or a qualified professional.
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