Penny Runs the NumbersA 2021 buyer of the median home (20% down at 2.96%) owes about $246,500 today with a $1,164 payment. Selling and buying the same $417,500 house again at today's 7.18% raises the payment to $1,924 (+$761 a month) and costs $37,575 in fees on day one. After 10 years the move has cost $167,071. The new rate would need to be 2.78% to break even, below the old rate.
What the calculator shows
Enter what your home is worth, what you still owe, your current rate and the years left. Then set the price of the next home and today's mortgage rate. The cards show both monthly payments, the break-even rate and how much moving has cost you after the number of years you pick on the chart.
The default numbers describe a typical 2021 buyer: the 2021 median existing-home price from the National Association of Realtors, 20% down, and the 2021 average 30-year rate from Freddie Mac's weekly survey. Today's rate and home value are the latest Freddie Mac and NAR figures.
Why the break-even rate is lower than the rate you have
Moving is not just a new rate. Selling costs about 6% of the price and buying another 3% (both are assumptions you can read in the sources). Those $37,575 come out of your equity, so the new loan is bigger than the old one: $284,075 instead of $246,500.
A bigger loan needs a lower rate to cost the same each month. Even stretched back to 30 years, the new loan only matches the old $1,164 payment at 2.78%. At 6% you would still pay $539 more a month, and at 3% about $34 more.
The downsizing math
If you want to move without paying more per month, the price of the next home is the lever. At today's 7.18%, the payment matches the old one at a home price of about $308,492, which is $109,008 (26%) less house than you have now.
The chart adds everything up over time: day-one fees, the higher payments and the slower payoff of a fresh 30-year loan. On the same house the gap reaches $324,956 by year 25, when the old loan would have been paid off.
Questions
Is it worth giving up a 3% mortgage?
In pure money terms, rarely for the same house. With the default inputs, moving raises the payment from $1,164 to $1,924 a month and leaves you $167,071 behind after 10 years. Moving can still be the right call for a job, family or space; the calculator shows the price tag.
What mortgage rate would make moving break even?
For the default 2021 buyer, 2.78%. That is below the 2.96% loan they already have, because selling and buying fees make the new loan larger.
How much cheaper does my next home need to be to keep the same payment?
At today's 7.18% rate, about $308,492 instead of $417,500, or roughly 26% less. Use the next home price slider to test your own numbers.
What does this calculator leave out?
It counts principal and interest only. It ignores property tax (which often resets higher after a purchase), insurance, PMI, moving costs, home price changes, refinancing and extra payments. Selling (6%) and closing (3%) costs are assumptions.
Sources and assumptions
- Today's 30-year fixed-rate mortgage average, week of 2026-11-05: Freddie Mac Primary Mortgage Market Survey (PMMS) (checked 2026-11-11)
- Average 30-year fixed rate in calendar year 2021 (mean of the 52 weekly PMMS readings) — the 'locked-in' rate: Freddie Mac PMMS history (PMMS_history.csv) (checked 2026-11-11)
- Median existing-home price, full year 2021 (used to derive the default loan balance): National Association of Realtors 2021 annual existing-home sales data (release of 2022-01-20; NAR page offline, link is NPR coverage of that release) (checked 2026-11-11)
- Current home value = today's median existing-home price, September 2026: National Association of Realtors, Existing-Home Sales (released 2026-10-13) (checked 2026-11-11)
- Principal and interest only: no property tax, insurance, PMI or HOA (these would be similar for the same house either way, but property tax often resets higher on a purchase).
- No home price appreciation: both homes keep today's value, so the 'cost of moving' is the gap in (home value - debt - cash paid) between moving and staying.
- The new home is financed with a 30-year fixed loan; all net sale proceeds go into the down payment and closing costs.
- Monthly compounding, payments at month end, no extra payments, no refinancing, no moving costs beyond the two percentages.
Last updated 2026-11-11.