Refinance Calculator
Enter your current loan balance, old rate, new rate, and closing costs to find your break-even month — the point when monthly savings recoup refinancing
Refinance Calculator
Calculator
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Formula: M = P[r(1+r)^n]/[(1+r)^n - 1] | Break-even = Closing Costs / Monthly Savings
Worked example — Save $269/mo, break-even in 19 months
Formula
M = P[r(1+r)^n]/[(1+r)^n - 1] | Break-even = Closing Costs / Monthly Savings
Standard amortization formula where P = principal, r = monthly rate (annual/12), n = total months. Break-even point shows when refinancing savings exceed closing costs.
Worked Examples
Example 1: 6.5% to 5.5% refi
Problem:$250,000 balance, 25yr remaining at 6.5%, refi to 5.5% 30yr, $5,000 closing
Solution:Old payment: $1,688. New: $1,419. Savings: $269/mo. Break-even: 19 months.
Result:Save $269/mo, break-even in 19 months
Frequently Asked Questions
When should I refinance?
Generally when you can lower your rate by 0.75-1% or more, plan to stay in the home past the break-even point, and closing costs are reasonable (typically 2-5% of loan).
What are typical closing costs?
Refinance closing costs typically range from 2-5% of the loan amount, including appraisal ($300-600), title insurance, origination fees, and recording fees.
What is the difference between a rate-and-term refinance and a cash-out refinance?
A rate-and-term refinance replaces the existing note with a new one of the same balance at a different rate or term, which is the case Refinance Calculator models. A cash-out refinance increases the balance and hands you the difference, so the new payment is driven partly by fresh borrowing rather than by the rate change. Break-even months are not comparable between the two, because a cash-out may raise the payment even when the rate falls.
How do discount points change the break-even calculation?
Discount points are prepaid interest that buys down the coupon, so they raise closing costs while enlarging the monthly saving. Both sides of the cost-divided-by-savings ratio move, and the net effect on the break-even month can go either way. Points generally pay off only over a long holding period, so they suit a borrower certain of staying with the loan and hurt one likely to refinance again or sell within a few years.
Why can my monthly payment fall while lifetime interest goes up?
Payment size depends on the balance, the rate and the number of months it is spread over. Refinancing a loan with 25 years left into a fresh 30-year term restarts the amortisation schedule, adding 60 payments, so the monthly figure drops even if total interest rises. The calculator flags this case. To compare wealth rather than cash flow, match the new term to the remaining term of the old note.
Is a no-closing-cost refinance genuinely free?
No. The lender either folds the fees into the balance or, more commonly, offers a higher rate and uses the resulting lender credit to pay them. Because out-of-pocket cost is near zero, the break-even ratio reports an implausibly short or infinite payback, which hides the fact that you are paying for the fees through every future month of a higher coupon. Compare the lifetime cost of both structures rather than the break-even alone.
How does loan-to-value ratio affect whether a refinance is worthwhile?
LTV is the balance divided by the appraised value, and lenders price rates in tiers against it. If appreciation and principal repayment have pushed your LTV below the threshold at which mortgage insurance can be dropped, cancelling that premium can add to the monthly saving beyond what the rate change alone delivers. A weak appraisal works the other way and can push the quoted rate up or disqualify the application.
Should I refinance into a shorter term instead of another 30-year loan?
A 15-year or 20-year refinance usually carries a lower rate and cuts total interest sharply, but the payment often rises rather than falls, so the classic break-even month is undefined and the right test becomes total interest saved against closing costs. Choose the shorter term only if the higher required payment is comfortable, since the commitment is contractual; making extra principal payments on a 30-year note achieves a similar result with more flexibility.
What is a mortgage recast and when is it better than refinancing?
A recast keeps the existing note, rate and maturity date but re-amortises the payment downward after you make a large lump-sum principal payment, usually for a modest administrative fee. It is the better option when your current rate is already below market, because refinancing would surrender that rate. It does not reduce your interest rate, so it cannot help a borrower whose goal is a cheaper coupon. Availability depends on the servicer.
Does restarting the amortisation schedule slow down equity build-up?
Yes. Early payments on any amortising mortgage are mostly interest, and the principal share grows over the term. Resetting to a new 30-year schedule returns you to the interest-heavy end of the curve, so the rate at which you build equity slows even though the payment is lower. Borrowers who want the rate cut without losing amortisation progress typically refinance into a term matching the years remaining on the original loan.
References
Background & Theory
History
Reviewed for accuracy by Sahil, Senior Finance & Tax Editor · Editorial policy
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