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Fixed vs ARM

Cheaper now. But what happens later?

An ARM starts below the fixed rate. The question is whether you'll be gone before it resets — and what the payment looks like if you're not.

Your numbers

$520,000
6.69%
30 yrs
10 yrs

ARM type

After the fixed period

Caps: 5% at the first reset, 2% per year after, 5% over the life of the loan.

Side by side

30-yr fixed

$3,352

6.69%

Same payment for the whole term.

7/1 ARM — start

$3,198

6.24%

Locked for 7 years.

ARM — worst case

$4,747

11.24%

Most it can reach after year 7.

Monthly savings while fixed
$154
Banked over the first 7 years
$12,906
Break-even after the reset
10 months
Total paid over 10 yrs — fixed
$402,240
Total paid over 10 yrs — ARM
$439,539

The honest read

Over 10 years, the ARM costs $37,300 more than the fixed.

Worst case, the payment goes from $3,198 to $4,747 — that's $1,395 a month more than the fixed. If that number would break you, take the fixed.

Year by year

Yr 16.24%$3,198
Yr 26.24%$3,198
Yr 36.24%$3,198
Yr 46.24%$3,198
Yr 56.24%$3,198
Yr 66.24%$3,198
Yr 76.24%$3,198
Yr 811.24%$4,747reset
Yr 911.24%$4,747
Yr 1011.24%$4,747

Mint bars are months the ARM is cheaper than the fixed. Red bars are months it isn't.

How to read this

ARM rates aren't published by the Fed anymore, so we estimate them as the live 30-year fixed minus a typical spread (0.45 points for a 7/1) — today's fixed anchor is 6.69% as of 2026-08-06. Your lender's actual ARM quote, margin, and index will differ. Refinancing or selling before the reset is the whole ARM bet — if you're not confident you'll be out in time, the fixed is the boring, safe answer. Run the full payment with taxes and insurance.

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Estimates only. Not an appraisal, tax advice, or lending offer. Checking here never touches your credit.