Calculated using standard mathematical and industry formulas.
Refinancing a mortgage replaces an existing loan with a new loan featuring a lower interest rate, different term length, or cash-out equity. A refinance is financially advantageous if new interest rates drop at least 0.75% to 1% below your current rate and monthly savings offset upfront closing costs (2%–5%) within your planned stay.
How to use this calculator?
Enter your current mortgage balance remaining.
Enter your existing interest rate and remaining years on your mortgage.
Enter the new offered interest rate, new loan term, and estimated closing costs.
Read your monthly payment savings, breakeven month, and net lifetime savings.
Formula & calculation method
Mortgage Refinance Amortization Equations
Monthly Savings = Current Payment - New Payment; Break-Even Point (Months) = Total Closing Costs / Monthly Savings
P = current balance, r = monthly rate, n = total months in loan term.
Step-by-step calculation example
$300,000 balance @ 6.5% (25 yrs) vs 5.25% (25 yrs) with $4,000 costs → Monthly payment drops from $2,025.26 to $1,797.77 (saves $227.49/mo). Breakeven in 18 months.
Key insights to remember
The breakeven point is the exact month where total monthly interest savings equal your upfront refinancing closing costs.
A general rule of thumb is that refinancing is worth considering if you can lower your interest rate by 0.75% to 1.00% or more.
Refinancing into a shorter term (e.g. 30-year to 15-year) may increase your monthly payment slightly but saves massive interest over the life of the loan.
Closing costs typically average 2% to 6% of the loan principal, covering appraisal fees, title insurance, and lender origination fees.
How to interpret your results?
Break-Even Horizon
If closing costs total $6,000 and monthly savings are $200, your break-even point is 30 months. You must stay in the home past that date for refinancing to save money.
Expert advice & guidance
💡 Refinancing tip: Request quotes from multiple lenders to leverage competitive closing cost credits. Lowering your interest rate by just 0.75% can save tens of thousands over the loan life.
Frequently asked questions
How much does it cost to refinance a mortgage?
Refinancing a mortgage costs between 2% and 5% of the total loan amount in upfront closing costs. On a $300,000 mortgage, closing fees typically range from $6,000 to $15,000, covering appraisal, title search, lender origination, and underwriting fees.
When should you refinance your mortgage?
Refinance your mortgage when prevailing market interest rates are at least 0.75% to 1.0% lower than your current rate, when removing mandatory private mortgage insurance (PMI), or to convert an adjustable-rate mortgage (ARM) into a fixed-rate loan before rates increase.
How long does it take to refinance a house?
Refinancing a home takes an average of 30 to 45 days from initial application submission to loan closing. Timeline factors include property appraisal scheduling, underwriting document verification, credit checks, and title insurance processing.
How soon can you refinance a mortgage after buying?
Conventional mortgages allow refinancing immediately after closing, though many lenders require a 6-month seasoning period. Cash-out refinances and government-backed FHA/VA streamline loans typically enforce a strict 6-month to 12-month waiting requirement.
Can you refinance a home equity loan or personal loan?
Yes, you can refinance home equity loans, HELOCs, and personal loans into a single consolidated mortgage or lower-rate personal loan. Refinancing replaces high-rate debt with lower interest charges, reducing monthly obligations or shortening repayment terms.
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