What Is Fixed-Rate Mortgage?
A fixed-rate mortgage locks your interest rate for the entire loan term, keeping your payment predictable. Learn how it works and when it's the right choice.
Definition
A fixed-rate mortgage is a home loan where the interest rate stays the same for the entire term -- typically 15 or 30 years. Your monthly principal and interest payment never changes, regardless of what happens to market interest rates. If you lock in a 6% rate on a 30-year fixed mortgage, you pay 6% for all 30 years, even if rates rise to 9% or fall to 3%.
The 30-year fixed-rate mortgage is by far the most popular loan type in America, accounting for roughly 90% of home loans. It offers the lowest monthly payment because the debt is spread over 360 months. The 15-year fixed mortgage has higher monthly payments but saves dramatically on total interest and builds equity faster.
Fixed-rate mortgages provide certainty: you always know what your principal and interest payment will be. However, your total monthly payment can still change if property taxes or homeowner's insurance increase (these are typically collected through escrow). The principal and interest portion, which is the largest component, never changes.
Real-World Example
You take a $300,000 30-year fixed mortgage at 6.5%. Your monthly principal and interest payment is $1,896 -- forever (or until you refinance or sell). If rates rise to 8% next year, you are protected. Your neighbor who bought the same house with an adjustable-rate mortgage at 5.5% initially pays $1,703, but when the rate adjusts to 8%, their payment jumps to $2,201. Your predictability came at a cost (higher initial rate) but provided peace of mind.
Why It Matters
Fixed-rate mortgages are the foundation of American homeownership because they eliminate interest rate risk. You can plan your budget for decades knowing your largest monthly expense will not surprise you. In a rising rate environment, a fixed rate is a significant advantage. In a falling rate environment, you can always refinance to a lower rate. For most homebuyers, the 30-year fixed is the right choice because it combines affordability with predictability.
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Frequently Asked Questions
Is a 15-year or 30-year fixed mortgage better?
A 15-year has higher payments but saves enormously on interest. On a $300,000 loan at 6%, a 15-year saves about $200,000 in total interest compared to a 30-year. Choose 15-year if you can afford the payments. Choose 30-year if you need lower monthly costs or want more cash flow flexibility.
Should I choose fixed or adjustable rate?
If you plan to stay in the home more than 5-7 years, a fixed rate is usually better because it eliminates the risk of rate increases. If you plan to move within 3-5 years, an adjustable rate (ARM) may save money because the initial rate is typically lower.
Can I get a fixed-rate mortgage with bad credit?
Yes, but at higher rates. FHA loans are available with credit scores as low as 580 (with 3.5% down). Conventional fixed-rate loans typically require 620+. Better credit scores get significantly better rates.
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