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How Mortgage Rates Work

📖 12 min read🏠 Real EstateUpdated April 2026

Table of Contents

  1. What Determines Your Mortgage Rate
  2. Credit Score Impact
  3. Down Payment & PMI
  4. Fixed vs. Adjustable (ARM)
  5. Buying Down Your Rate
  6. How to Shop Lenders
  7. Use the Mortgage Calculator

What Determines Your Mortgage Rate

Mortgage rates aren't random. They're based on a mix of economic factors, your personal financial profile, and the type of loan you choose. Here's what affects the rate lenders offer you:

How Credit Score Affects Your Rate

Your credit score is one of the biggest factors in the rate you get. Here's a general breakdown for a $300,000 30-year conventional mortgage:

Credit ScoreEst. Rate (2026)Monthly PaymentTotal Interest (30yr)
760–850~6.5%~$1,896~$382,000
700–759~6.8%~$1,966~$408,000
680–699~7.2%~$2,035~$433,000
620–679~7.8%~$2,160~$478,000
580–619~8.5%~$2,306~$530,000

A 100-point difference in credit score can mean $100+ per month on a typical mortgage — that's $36,000+ over 30 years.

💡 Pro tip: If your score is below 700, it may be worth delaying a few months to improve it before applying. Even a 20-point improvement can meaningfully lower your rate.

Down Payment & PMI

Most conventional loans require at least 5% down. But putting down 20% or more means:

📌 Example: 20% vs 5% Down on $350,000 Home

5% down ($17,500): Loan = $332,500 at 7.0% → Payment ≈ $2,213/mo + ~$180 PMI = ~$2,393/mo

20% down ($70,000): Loan = $280,000 at 7.0% → Payment ≈ $1,863/mo (no PMI)

Monthly savings: $530/month × 12 months × 30 years = $190,800 saved

Fixed vs. Adjustable Rate Mortgages

30-year fixed rate is the most popular — your rate stays the same for the entire life of the loan. Your payment is predictable and won't change even if rates rise.

5/1 or 7/1 ARMs offer a lower initial rate for 5 or 7 years, then adjust annually after that. They make sense if you plan to sell or refinance before the adjustment period begins.

Feature30-Year Fixed5/1 ARM
Initial rate7.0%5.9%
Rate cap after initialNone (rate is fixed)+2% per year, +5% lifetime
Best forMost buyers — stabilityShort-term owners (5–7 yr)
Risk levelLowMedium-High

Buying Down Your Rate (Discount Points)

One point = 1% of your loan amount, paid upfront. It typically reduces your rate by 0.25%–0.5%. On a $300,000 loan, one point costs $3,000.

Is it worth it? If you stay in the home for 5+ years, buying 1–2 points often pays off. Run the numbers with our mortgage calculator to see your break-even point.

How to Shop for the Best Rate

  1. Get quotes from 3–5 lenders — Banks, credit unions, and online lenders. Each will give you a Loan Estimate (LE) form.
  2. Compare the APR, not just the interest rate. APR includes fees and gives you the true cost comparison.
  3. Watch out for junk fees — Application fee, processing fee, underwriting fee, rate lock fee. Some lenders charge these, some don't.
  4. Check for lender credits — Sometimes you can accept a slightly higher rate in exchange for the lender paying your closing costs.
  5. Don't let one quote pressure you — Shop confidently. Getting multiple quotes within 30 days only counts as one hard inquiry on your credit.

Try It Yourself

Calculate Your Monthly Mortgage Payment

Enter your home price, down payment, and rate to see your estimated payment.

Open Mortgage Calculator →
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