How conventional mortgage refinancing works
A conventional rate-and-term refinance allows homeowners to replace an existing mortgage with a new loan conforming to Fannie Mae and Freddie Mac underwriting standards. By securing a lower interest rate, shortening your loan term, or adjusting your amortization schedule, refinancing can significantly reduce your monthly payments and overall borrowing expenses.
Refinancing requires paying upfront lender closing costs, which typically range between 1.5% and 3% of the loan amount. These fees cover origination points, underwriting, home appraisal, title insurance, and recording fees.
To determine whether refinancing makes financial sense, borrowers calculate the break-even period: the number of months of lower monthly payments needed to recover the out-of-pocket closing costs. If you plan to remain in your home past the break-even date, refinancing delivers net savings.
Worked example: Refinancing a $320,000 conventional mortgage from 7.25% to 6.00%
Consider a homeowner with a $320,000.00 remaining balance on a conventional mortgage at a 7.25% interest rate with 300 months left to pay.
Under the existing mortgage, the current monthly payment is $2,312.98, and the interest if you keep your loan totals $373,894.59 over the remaining 25 years.
The borrower refinances into a new 300-month conventional mortgage at a 6.00% interest rate, requiring $5,000.00 in upfront closing costs and fees.
The new monthly payment drops to $2,061.76, generating a change in monthly payment of $251.22 in monthly cash flow relief.
Total interest on the new loan equals $298,529.35, resulting in a net saving after switching costs of $70,365.24.
Dividing the $5,000.00 closing costs by the $251.22 monthly savings reveals that the months to earn back the costs is 20 months.
When does refinancing make sense?
A longstanding rule of thumb suggests refinancing is worthwhile when prevailing market rates are at least 0.75% to 1.00% below your existing note rate. However, even a 0.50% reduction can produce substantial savings on larger conforming or high-balance loan amounts.
Homeowners who have built 20% or more home equity can also use a conventional refinance to eliminate costly private mortgage insurance (PMI) from an earlier low-down-payment purchase, generating immediate monthly savings regardless of interest rate movements.
Inputs for the Conventional loan refinance calculator
Balance left on your loan
The outstanding principal balance remaining on your existing mortgage from your latest loan statement.
Current interest rate
The annual nominal interest rate you are currently paying on your existing mortgage.
Months left
The number of monthly payments remaining on your current mortgage (for example, 300 months for 25 years).
New interest rate
The annual interest rate offered on the proposed new conventional refinancing mortgage.
New loan term
The duration of the new mortgage in months (commonly 180 months for 15 years, or 360 months for 30 years).
Closing costs and fees
All upfront lender fees, title charges, appraisal fees, and settlement costs required to complete the refinance.
CALCULATOR QUESTIONS
Conventional mortgage refinance questions
How long does it take to break even on a conventional mortgage refinance?
The break-even timeline is calculated by dividing your total upfront closing costs by your monthly payment reduction. In our typical example with $5,000 in closing costs and a $251.22 monthly saving, the break-even period is 20 months.
Can I roll my refinancing closing costs into the new loan balance?
Yes. Most conventional lenders permit 'no-cost' or financed refinances where closing costs are rolled directly into the new principal balance, provided the resulting total loan amount complies with Fannie Mae and Freddie Mac loan-to-value (LTV) limits.
Does refinancing reset my 30-year mortgage timeline?
If you refinance into a standard 30-year mortgage after already paying several years on your original loan, you extend your overall repayment period. To avoid extending your payoff date, match the new term to your remaining months or choose a 15-year or 20-year term.
Can I eliminate PMI by refinancing my conventional loan?
Yes. If your property has appreciated or you have paid down principal so that your loan-to-value ratio is 80% or less, a new conventional refinance will be completely free of private mortgage insurance.