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Fixed-rate vs ARM — which mortgage type fits when
Two-thirds of US homebuyers pick a 30-year fixed-rate mortgage by default. That's often correct — but not always. The fixed-vs-ARM choice hinges on how long you'll hold the loan, where rates are heading, and how much certainty you're willing to pay for. Here's what the four common loan structures actually mean.
Published 2026-04-25 · Last reviewed 2026-04-27 · methodology
30-year fixed — the default
Same interest rate and payment for 30 years. Most expensive in monthly cost relative to a 15-year, but lowest payment for the loan amount. Roughly 70% of US conventional mortgages by 2024 Federal Reserve data.
Best for: buyers who plan to stay 7+ years AND value payment certainty. The rate premium vs. an ARM is the price of insurance against future rate increases.
15-year fixed — half the time, much less interest
Same rate concept as 30-year but amortized over 15. Total interest paid is roughly one-third of a 30-year on the same principal. Monthly payment is ~40-50% higher.
Best for: buyers with strong income who want to be debt-free at retirement OR plan to refinance into another home eventually. Rates are typically 0.4-0.7% lower than 30-year fixed because lender risk is shorter.
Hybrid ARMs — 5/1, 7/1, 10/1
Adjustable-rate mortgages with an initial fixed period (5, 7, or 10 years) then annual adjustments. The first number is the fixed period in years; the second is how often it adjusts after that.
5/1 ARM: fixed for 5 years, then re-prices every 12 months based on a benchmark index (typically SOFR) plus a margin (typically 2.25-3.0%).
Initial rates are usually 0.5-1.5% below 30-year fixed. After the fixed period, the rate can adjust up or down — capped per-adjustment (typically 2%) and lifetime (typically 5%).
Best for: buyers planning to sell or refinance before the fixed period ends. If you're 90% sure you'll move within 7 years, a 7/1 ARM saves real money.
The 2026 rate landscape
30-year fixed hovered between 6.5% and 7.5% through most of 2024-2026. ARMs were 5.75-6.5% initial. The fixed-ARM spread tightened to ~0.75% as the Fed signaled rate cuts.
Refinancing math: if rates drop 1%+ AND you'll stay 3+ more years, refinance is worth the closing costs (typically 2-3% of loan value).
What zipradar shows
We don't quote mortgage rates — those are lender-specific and change daily. We focus on the property-side data (taxes, flood, schools, crime) that affects which monthly payment you can actually afford in a given zip.
Pair our /topic/property-tax/[zip]/ rollups with a lender quote to model your real PITI (Principal + Interest + Taxes + Insurance).
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