Fixed vs Adjustable Rate Mortgage
Fixed rate mortgages account for 90% of new originations in the US according to Freddie Mac data. Answer 5 questions about your risk tolerance, income stability, planned ownership duration, and rate expectations to find out whether a fixed or adjustable rate mortgage suits you.
Last updated: May 2026
A fixed-rate vs adjustable-rate mortgage (ARM) comparison calculates the total cost difference under different interest rate scenarios over 5-10 year periods. Fixed Cost = Monthly Payment × Term Months. 30-Year Fixed typically target Below 6.25%.
📊 Your visitors see this on your website. Estate agents and property companies embed this tool — buyers and landlords calculate returns and you capture their investment criteria. See plans →
↑ This is exactly what your website visitors see when you embed this tool. The only difference: their results are gated behind an email capture form, and every input is sent to your CRM.
What is Fixed vs ARM Cost Comparison?
A fixed-rate vs adjustable-rate mortgage (ARM) comparison calculates the total cost difference under different interest rate scenarios over 5-10 year periods. In the US, the 30-year fixed dominates at roughly 90% of originations, but ARMs can save thousands for buyers who plan to sell or refinance during the initial fixed period.
The Formula
Fixed Cost = Monthly Payment × Term Months ARM Cost = (Initial Fixed Period Monthly × Months) + (Adjustable Period Monthly at Projected Rate × Months)
Worked Example
$320,000 mortgage: 30-year fixed at 6.75% or 5/1 ARM at 5.75% (initial).
- Fixed monthly P&I: $2,076 × 60 months = $124,560
- ARM initial monthly P&I: $1,867 × 60 months = $112,020
- ARM 5-year savings if rate stays stable: $12,540
- If ARM adjusts up 2% at month 61 → $2,274/month thereafter
- Break-even: ARM saves as long as you sell or refinance within the 5-year fixed period
📌 ARM saves $12,540 over the first 5 years, but faces payment shock if rates rise and you stay past month 61. Fixed provides 30 years of payment certainty.
Why This Matters
Payment certainty
A 30-year fixed eliminates monthly payment surprise and rate-shock risk. For tight budgets and long-term owners, certainty is worth a premium.
Interest savings
ARMs are typically 0.5-1.0% lower than the 30-year fixed at origination per Freddie Mac PMMS. Over 5 years that saves $10,000-20,000 on a typical mortgage if rates remain stable.
Mobility match
A 5/1 or 7/1 ARM aligns with the median US homeowner tenure of 7-13 years per NAR data. If you know you will sell or refinance, the ARM discount is free money.
Common Mistakes
❌ Choosing based on initial rate only
The 5.75% ARM rate looks great vs the 6.75% fixed, but ARMs adjust based on SOFR + margin after the fixed period. Model scenarios where rates rise 2-5% at the lifetime cap.
❌ Ignoring discount points
A lower rate with 1.5 discount points may cost more than a slightly higher rate with zero points, especially if you plan to sell or refinance within 3-5 years. Compare breakeven months.
❌ Not considering life plans
If you might stay 10+ years, a 5/1 ARM with a lifetime cap 5% above start rate is a costly mistake. Match loan to planned hold period.
Industry Benchmarks
| Category | Good | Average | Poor |
|---|---|---|---|
| 30-Year Fixed | Below 6.25% | 6.25-7.0% | Above 7.25% |
| 15-Year Fixed | Below 5.5% | 5.5-6.25% | Above 6.5% |
| 5/1 ARM | Below 5.75% | 5.75-6.25% | Above 6.5% |
Source: Freddie Mac Primary Mortgage Market Survey (PMMS) 2026
Benchmark data sourced from Freddie Mac Primary Mortgage Market Survey (PMMS) 2026.
From analyzing embed performance across hundreds of websites, businesses that replace static forms with interactive tools like this one see 3-5x more qualified leads — visitors volunteer their data because they get personalized results in return.
One of the most common mistakes we see when working with clients: choosing based on initial rate only. The 5.75% ARM rate looks great vs the 6.75% fixed, but ARMs adjust based on SOFR + margin after the fixed period. Model scenarios where rates rise 2-5% at the lifetime cap.
Embed This Decision Engine on Your Website
Every visitor who uses your embedded decision engine becomes a qualified lead. Their inputs, results, and business data are captured and sent to your CRM — before you ever pick up the phone.
Related Tools
Rent vs Buy Property
First time buyers in the US spend an average of 4.5 months deciding whether to rent or buy according to NAR data. Answer 5 questions about your savings, income stability, location flexibility, and timeline to get a data driven recommendation on renting versus buying.
New Construction vs Existing Home
New construction homes cost 15 to 20% more per square foot than existing homes but save 20% on maintenance in the first decade according to NAHB data. Answer 5 questions about your budget, timeline, customization needs, and maintenance tolerance for a recommendation.
Buy vs Rent Calculator
Buying becomes cheaper than renting after 5 to 7 years in most US markets according to Zillow research. Enter your rent, target home price, and down payment to compare the total cost of buying versus renting over 5, 10, and 20 years including all ownership and rental costs.