Fixed vs Variable Rate Mortgage
Compare fixed and variable (adjustable) rate mortgages. See payment scenarios, break-even points, and risk analysis.
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What is Fixed vs Variable Rate Mortgage?
The fixed vs adjustable-rate mortgage decision hinges on your time horizon, risk tolerance, and interest rate outlook. Fixed-rate mortgages offer payment certainty for the full loan term. Adjustable-rate mortgages (ARMs) offer a lower initial rate — typically 0.5-1.5% less — but carry the risk of rate increases after the initial fixed period. This calculator models both scenarios, showing the break-even point where ARM savings offset potential rate increases.
Which is Better for You?
The right choice depends on your specific situation. Here are the most common decision scenarios:
You plan to stay in the home 10+ years
Payment certainty over a long horizon is valuable. ARM rates can increase significantly after the initial period, potentially exceeding the fixed rate.
You plan to move or refinance within 5 years
The lower initial ARM rate saves money during the fixed period. If you sell or refinance before the rate adjusts, you capture the savings without the adjustment risk.
Interest rates are expected to decrease
ARMs adjust with market rates. If rates drop, your payment drops automatically (within caps). A fixed rate locks you into the higher rate unless you refinance.
You want payment predictability for budgeting
Your payment never changes for the life of the loan. This makes budgeting easier and eliminates the stress of potential payment increases.
Related Comparisons
For authoritative guidance, see CFPB — Adjustable-Rate Mortgages Explained.
Frequently Asked Questions
What is a 5/1 ARM?
A 5/1 ARM has a fixed rate for the first 5 years, then adjusts annually based on a benchmark index (typically SOFR) plus a margin. The initial rate is usually 0.5-1.5% lower than a comparable fixed-rate mortgage. Rate caps limit how much the rate can increase per adjustment and over the loan's lifetime.
How much can an ARM rate increase?
Most ARMs have three caps: initial adjustment cap (typically 2%), periodic cap (2% per year), and lifetime cap (5-6% above the initial rate). So a 5.5% ARM could potentially reach 10.5-11.5% over its lifetime, though this is rare.
When is a fixed rate better?
When rates are historically low (lock in the low rate), when you plan to stay long-term, when you can't tolerate payment uncertainty, or when the fixed-to-ARM rate spread is small (under 0.5%). If rates are already low, there's less upside to an ARM.
Can I refinance an ARM to a fixed rate later?
Yes, but you'll pay closing costs (2-5% of loan amount) and the fixed rate available at that time may be higher than today's. There's no guarantee you'll be able to refinance at a favorable rate when your ARM adjusts.
The tools and calculators provided on The Simple Toolbox are intended for educational and informational purposes only. They do not constitute financial, legal, tax, or professional advice. While we strive to keep calculations accurate, numbers are based on user inputs and standard assumptions that may not apply to your specific situation. Always consult with a certified professional (such as a CPA, financial advisor, or attorney) before making significant financial or business decisions.
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