Real Life Math
Mortgage Rates 2026: 2.65% vs 7.40% — $417,000 More Interest
Mortgage rates 2026: Freddie Mac's 30-year fixed rate is 7.40% (Oct 15, 2026). The record low was 2.65% in January 2021. On the same $400,000, 30-year loan, …
Ages 13–17 · US Grade 7 1:50
Step by step
- Same house, same loan: $417,000 more interestSame house. Same loan. One buyer pays four hundred seventeen thousand dollars more in interest.
- Mortgage rate: % per year charged on what you still oweThe only difference: the mortgage rate. The percent per year the bank charges on what you still owe.
- Freddie Mac: 2.65% (Jan 2021, record low) → 7.40% (Oct 15, 2026)Freddie Mac's weekly numbers: two point six five percent in January twenty twenty-one, a record low. Now: seven point four zero.
- Rate × 2.8 → interest × ?The rate went up less than three times. Does the interest just triple? Take a guess.
- $400,000 · 30 years: $1,612 a month at 2.65% … at 7.40%?Borrow four hundred thousand dollars for thirty years. At two point six five, you pay one thousand six hundred twelve a month. At seven point four zero...
- $2,770 a monthtwo thousand seven hundred seventy.
- 360 payments: $180,000 of interest …Over three hundred sixty months, the interest adds up to one hundred eighty thousand dollars...
- … vs $597,000 · × 3.3versus five hundred ninety-seven thousand. That's three point three times.
- 1st month's interest = what you owe × rate ÷ 12Why? Look at the first payment. Interest is what you owe, times the rate, divided by twelve.
- 2.65%: $883 of $1,612 → 55% is interestAt two point six five: eight hundred eighty-three dollars. Just over half the payment.
- 7.40%: $2,467 of $2,770 → 89% is interestAt seven point four zero: two thousand four hundred sixty-seven. Eighty-nine percent of the payment!
- After 10 years you still owe $346,000 (vs $300,000)So the balance barely drops. Ten years in, you still owe three hundred forty-six thousand, not three hundred.
- High rate → slow payoff → interest on a big balance for yearsHigher rate, slower payoff. So you pay interest on a big balance for years longer.
- On a test: owe × rate ÷ 12 · ÷ payment · payments − loanOn a test: what you owe, times the rate, over twelve. Divide by the payment for the share. Total interest: all the payments, minus the loan.
- On a test: $200,000 at 6% a year · 1st month's interest?On a test, it looks like this: two hundred thousand dollars at six percent. First month's interest?
- See a loan rate → think: what you owe × rate, every monthSee a loan rate? Think: what you owe, times the rate, every month.
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