Fixed-Rate vs Adjustable-Rate Mortgages Compared
How fixed-rate and adjustable-rate mortgages work, how payments can change, the pros and cons of each and the questions to ask before choosing a loan.
A fixed-rate mortgage keeps the same interest rate, and usually the same payment, for an agreed period. An adjustable-rate mortgage, also called a variable or tracker rate in some places, can change over time with a benchmark rate. Fixed rates offer certainty, while adjustable rates can start cheaper but carry the risk that your payment rises.
How a fixed-rate mortgage works
With a fixed rate, the interest rate is locked for a set period. That might be a few years or the whole loan term, depending on where you live and what lenders offer. Your payment stays the same during that time, whatever happens to rates in the wider economy.
This makes budgeting easier. The trade-off is that fixed rates can start higher than adjustable ones, and if rates fall, you may not benefit unless you switch. Switching can involve fees or early repayment charges.
When a fixed period ends, many loans move to the lender's standard variable rate, which can be noticeably higher. Note the end date and review your options a few months before it arrives.
How an adjustable-rate mortgage works
An adjustable rate is usually made up of a benchmark rate plus a margin set by the lender. When the benchmark moves, your rate moves too, often at set reset dates. Some adjustable loans start with a lower introductory rate that later changes.
Key terms to understand:
- Benchmark: the reference rate your loan follows
- Margin: the fixed amount the lender adds on top
- Reset period: how often the rate can change
- Caps: limits on how much the rate can rise at each reset or overall
- Floor: a minimum rate the loan will not fall below
Also check how often the lender recalculates your payment and how much notice you receive. A payment that can change every month is harder to plan around than one that changes once a year.
Side-by-side comparison
| Feature | Fixed rate | Adjustable rate |
|---|---|---|
| Payment during the fixed or reset period | Stays the same | Can rise or fall |
| Starting rate | Often higher | Often lower |
| Budget certainty | High | Lower |
| Benefit if rates fall | Only by switching | Automatic, down to any floor |
| Risk if rates rise | Protected during fixed period | Payment goes up |
| Early repayment flexibility | Often limited or charged | Often more flexible |
These are general patterns. Individual loans differ, so compare the actual terms you are offered.
Some lenders also offer hybrid or split loans. A hybrid starts with a fixed period and then becomes adjustable, while a split loan lets you fix part of the balance and leave the rest variable. These can balance certainty and flexibility, but read the terms carefully.
How much can payments change?
Small rate changes make a big difference on large loans. Take a 200,000 loan repaid over 25 years. At 5% interest, the monthly payment is about 1,169. If the rate rises to 7%, it becomes about 1,414, an increase of roughly 245 a month.
That is why stress-testing matters. Before choosing an adjustable loan, work out whether you could still afford the payment if the rate rose by two or three percentage points. If the answer is no, a fixed rate may suit you better. Remember too that when rates rise, more of each payment goes to interest, so your loan balance falls more slowly.
Which might suit you
Neither option is right for everyone. Your choice depends on your budget, your plans and how much uncertainty you can handle. Try not to base it on a guess about future rates, which are hard to predict even for professionals.
A fixed rate may suit you if:
- You want a predictable payment for budgeting
- Your budget has little room for increases
- You plan to stay in the home for the fixed period
An adjustable rate may suit you if:
- You have a comfortable buffer in your budget
- You expect to sell or repay early
- You understand and accept the risk of higher payments
Questions to ask your lender
Get answers in writing before you sign.
- How long is the rate fixed, and what happens after that?
- What benchmark does the adjustable rate follow, and what is the margin?
- Are there caps or floors, and how do they work?
- What fees apply if I repay early, overpay or switch?
- What would my payment be if rates rose by two or three points?
Mortgage products and consumer protections vary by country. Your banking regulator or consumer-protection agency may publish plain-language guides on how home loans work where you live.
The bottom line
Fixed rates trade a possibly higher starting cost for certainty. Adjustable rates may start lower but pass the risk of rising rates to you. Compare the full terms, including caps, reset dates and early repayment fees, stress-test your budget against higher rates and choose the loan you could afford in a less comfortable scenario, not just today's.
Frequently asked questions
Which is cheaper, a fixed or adjustable mortgage?
It depends on how rates move after you borrow, which no one can know for sure. Adjustable loans often start with a lower rate, but they can become more expensive if rates rise.
Can I switch from an adjustable to a fixed rate later?
Often yes, by refinancing or switching products with your lender. This may involve fees, a new application and early repayment charges, so check the costs first.
What is a rate cap?
A cap limits how much an adjustable rate can rise, either at each reset or over the life of the loan. Not all loans have caps, so ask your lender to explain them in writing.
Do fixed-rate mortgages stay fixed for the whole loan?
In some countries the rate can be fixed for the full term, while in others it is fixed for a shorter period before moving to a variable rate. Check what is common in your market.
Disclaimer: This guide is general information, not financial advice. Rates, fees, rules and products differ by country and provider and change over time. Check the current terms with the provider, and consider a qualified, licensed adviser before you make a financial decision. Read our full disclaimer.
