Refinance sense check: payment drop vs new interest cost
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By Editorial team
You owe about $278,577 with 22 years left on a 6.875% note in our baseline tab. A restart quote adds $6,000 of closing costs rolled in, lifts the balance to $284,577, and drops the rate to 5.875% on a fresh 30-year amortization. Month-one P&I falls from about $2,050 to $1,683, a $367/month difference that is easy to notice. On payment savings alone, you recover the $6,000 in roughly 16 months ($6,000 ÷ $367). Yet total modeled interest jumps from about $262,522 on the remaining old track to $321,440 on the new loan because you pay the bank for eight extra years. This scenario is for homeowners weighing payment relief against the long-run cost of resetting the clock.
The scenario modeled
Home values are not modeled here. Each tab encodes the remaining loan balance directly so the comparison focuses purely on rate, term, and closing costs. No taxes, insurance, or MI in either tab so the payment-versus-interest contrast is easy to read.
| Input | Keep loan | Refinance |
|---|---|---|
| Loan balance modeled | $278,577 | $284,577 |
| Rate | 6.875% | 5.875% |
| Remaining term | 22 years | 30 years (reset) |
| Closing costs | None modeled | $6,000 rolled in |
The findings
A lower payment does not always mean a better deal. When amortization resets to 30 years, you pay the bank for eight additional years, which more than offsets the rate savings in this scenario. Pair this calculator view with a timeline: if you move in three years, the $367/month payment relief is the number that matters. If you stay for the full term, the $58,918 in extra lifetime interest is the one that does.
| Keep | Refinance | Difference | |
|---|---|---|---|
| Month 1 P&I | $2,050 | $1,683 | $367/month lower after refi |
| Total interest (modeled) | $262,522 | $321,440 | $58,918 more if you restart |
| Cash break-even (payment savings vs costs) | - | ~16 months ($6,000 ÷ $367/mo) | Lifetime interest tells the opposite story |
US context
Freddie Mac's weekly Primary Mortgage Market Survey tracks average 30-year fixed rates going back to 1971. It is a useful benchmark for comparing your refinance quote to the broader market, but the national average does not reflect your credit profile, lender, or the points built into your specific offer. Your actual break-even depends on those inputs, not the headline rate.
Source: Freddie Mac, "Primary Mortgage Market Survey," accessed April 2026. URL: https://www.freddiemac.com/pmms
When this comparison applies, and when it does not
Helpful when you already have a payoff quote and a Closing Disclosure from a lender, and want to understand the payment-versus-interest trade-off before you sign.
Weak when you ignore escrow changes, skip MI removal opportunities that come with the refinance, or are doing a cash-out refi where the larger balance changes the math entirely. Add those dollars before treating the comparison as complete.
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Frequently asked questions
- How do I know if refinancing makes sense?
- Compare monthly payment relief, closing costs, how many months of savings repay those costs, and whether you reset the amortization clock. Lower payments can still add lifetime interest if you stretch the term.
- What is a refinance break-even period?
- Divide lender fees and third-party costs by the monthly payment reduction. If you save $367 per month after a $6,000 cost roll-in, rough cash break-even is about 16 months on payment savings alone.
- Should I refinance into another 30-year loan?
- Only if cash flow is the priority. In our modeled example, the new 30-year note cut the payment but increased total interest versus staying on the remaining 22-year schedule.
- Do I need a new appraisal to refinance?
- Often yes for conventional loans, but agency streamline programs and property inspection waivers vary. Your lender sets the requirements; the calculator handles the math once you know rate, balance, and costs.