Loans and debt guide
Fixed vs. Variable Interest Rates
The rate structure describes whether the interest rate stays the same or can change under the agreement.
Fixed rate
A fixed rate remains constant during the period specified by the contract, making scheduled principal-and-interest payments more predictable.
Variable rate
A variable rate can change according to an index, margin, adjustment schedule, caps, and other contract terms. Payment or payoff time may change.
Compare the full terms
Review introductory periods, adjustment limits, fees, and how payment changes are handled. This guide is general education, not a recommendation.
Worked example
For a simple offer comparison, a $100,000 30-year loan at a constant 5% rate has principal-and-interest payments of about $536.82 per month; at 6%, the payment is about $599.55. This compares hypothetical fixed-rate loans and does not model an adjustable-rate reset.
Frequently asked questions
Can a variable-rate payment change?
It can, based on the agreement’s index, margin, adjustment schedule, and limits.
Does a fixed rate mean every housing cost stays fixed?
No. Taxes, insurance, and other costs can change even when principal and interest do not.
Sources and further reading
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Educational content only; not individualized financial, tax, or legal advice.