Mortgage Refinance Calculator — Break-Even & Total Savings

Compare your current mortgage with a refinance. Estimate monthly savings, remaining interest, closing-cost break-even time, and total lifetime savings.

Mortgage refinance rate comparison example

Example: $300,000 balance, 25 years remaining, current rate 7.00%, new 25-year term, and $6,000 in closing costs. Values are rounded estimates.

New rate New monthly payment Monthly savings Break-even Lifetime savings
6.50% $2,026 $95 64 months $22,415
6.00% $1,933 $187 33 months $50,230
5.50% $1,842 $278 22 months $77,423

Tips for comparing a refinance

  • Compare the annual percentage rate and the full fee disclosure, not only the advertised interest rate. Discount points and lender credits can materially change the break-even date.
  • Use the time you realistically expect to keep the property or loan. A refinance that saves money over 25 years can still lose money if you sell or refinance again before closing costs are recovered.
  • Keep the new term close to the years remaining when you want a fair total-cost comparison. Resetting a 20-year balance to 30 years often lowers the payment while increasing lifetime interest.
  • Run several rate and fee combinations. A slightly higher no-cost rate may beat a lower rate with expensive points when your expected holding period is short.

Mortgage refinance questions

There is no universal percentage-point rule. The useful threshold depends on your balance, years remaining, fees, new term, and how long you will keep the loan. A modest reduction can work for a large balance with low fees, while a larger reduction may still fail with high costs or a short holding period.

This tool divides closing costs by the estimated monthly payment savings. For example, $6,000 of costs divided by $200 of monthly savings produces a 30-month simple break-even point. If the new payment is not lower, a monthly-savings break-even does not exist.

Some lenders let borrowers finance certain costs, but doing so increases the new principal and the interest paid on those costs. This calculator treats costs as paid upfront so the fee impact remains visible. If you plan to finance them, add the financed amount to the balance for a conservative comparison.

Yes. Extending the repayment term can spread the balance across many more payments. The monthly amount may fall while additional years of interest and closing costs make the lifetime total higher. Compare both figures before choosing.
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Why a lower mortgage payment does not always mean a cheaper loan

A refinance replaces the remaining balance of an existing mortgage with a new loan. The new payment depends on both the rate and the newly selected term. Lowering the rate reduces interest, but stretching the balance over more months can reduce the payment even when the borrower ultimately pays more. That is why this calculator presents monthly cash flow and lifetime cost separately.

Closing costs create a second trade-off. The simple break-even period divides upfront costs by monthly savings and estimates how long it takes for the monthly benefit to repay those costs. It is a useful first screen, but it does not include the investment return that the upfront cash might otherwise earn, tax effects, or the possibility of selling the home.

The most useful comparison keeps the same balance and tests several combinations of rate, term, and fees. If one option has a lower total cost within the time you expect to keep the loan, it may be financially attractive. The final decision should still use the lender's official disclosure because APR, escrow, mortgage insurance, and prepayment rules vary by product and country.