Refinance Savings Calculator
How much will refinancing actually save you? Compare total interest over the life of both loans and see net savings after closing costs.
How Refinance Savings Add Up
When you refinance, you replace your current loan with a new one. The savings come from paying less interest over time, but the calculation isn't always obvious because you might change the loan term too.
Example: You owe $280,000 at 6.5% with 25 years left. Over those 25 years, you'll pay $276,000 in interest. Refinance to 5.25% for 30 years, and you pay $265,000 in interest. That's $11,000 saved, minus $5,000 in closing costs, for a net gain of $6,000.
But notice the term extended from 25 to 30 years. Your payment dropped from $1,901 to $1,547—great for cash flow—but you're paying off the loan slower. If you plan to stay for the full 30 years, the savings are real. If you sell in 10 years, recalculate based on what you'd actually pay over that shorter timeframe.
Term Length and Total Interest
Shortening your loan term saves massive amounts of interest. If you owe $280,000 at 6.5% with 25 years left and refinance to 5.25% for 15 years, you pay only $139,000 in total interest—a savings of $137,000 compared to your current loan. Your payment goes up to $2,263, but you're mortgage-free in 15 years instead of 25.
Extending the term does the opposite. Refinancing from 25 years to 30 years at the same rate would actually increase your total interest, even though your payment drops. The lower payment feels good now, but you pay interest for five extra years. Always compare apples to apples—same term to same term—or account for the time difference in your decision.
Some borrowers refinance to a longer term but keep making their old payment. You get the safety of a lower required payment if money gets tight, but you pay off faster by voluntarily paying more. That flexibility has value, especially if your income varies or you have young kids and uncertain expenses ahead.
Closing Costs and Net Savings
Gross savings numbers look impressive, but closing costs eat into them. A refinance that saves $40,000 in interest sounds great until you subtract $6,000 in costs. Your net savings is $34,000—still good, but not as dramatic as the headline number.
Lenders sometimes advertise no-closing-cost refinances. They cover the upfront fees by charging a higher interest rate—typically 0.25% to 0.5% more. On a $280,000 loan, that extra 0.375% costs you about $50/month or $18,000 over 30 years. If actual closing costs would have been $5,000, you just paid $13,000 extra to avoid upfront costs. The math rarely works in your favor unless you're selling or refinancing again within five years.
Always ask for a Loan Estimate from multiple lenders. Closing costs vary wildly—some lenders charge $3,000, others charge $7,000 for the same loan. Shop around, negotiate, and factor the true cost into your savings calculation. A slightly higher rate with lower costs can beat a lower rate with expensive fees.
Frequently Asked Questions
Is it worth refinancing to save $50/month?
Depends on closing costs and how long you stay. If $50/month costs $3,000 to achieve, you break even in 5 years. Over 15 years, you save $9,000 net. Run the full calculation to decide.
Should I extend my loan term when refinancing?
Only if you need lower payments for cash flow. Extending from 25 years left to a new 30-year loan reduces payments but often increases total interest, even at a lower rate.
What if I plan to sell in 5 years?
Calculate savings over just those 5 years, not the full loan term. You won't pay interest for years 6-30 if you sell, so lifetime comparisons overstate the benefit.
Can I refinance if my home value dropped?
Yes, but you need sufficient equity. Most lenders require at least 20% equity (80% LTV). If your home is worth less than you owe, you're limited to government programs like HARP (if eligible).
Do I save more refinancing early or late in my loan?
Early. You pay the most interest in the first years of a mortgage. Refinancing in year 2 saves far more than refinancing in year 22 because there's more interest left to cut.