Mortgage Overpayment Calculator
See how much interest you’ll pay over the life of your mortgage — and how small changes can save you thousands.
This simple calculation helps explain why many homeowners end up paying far more than expected.
Frequently Asked Questions About Mortgage Interest & Refinancing
How much interest do most homeowners really pay over a mortgage?
Most homeowners pay tens of thousands of dollars in interest over the life of a 30-year mortgage. In many cases, the total interest paid can be equal to or even higher than the original loan amount, especially when rates are above average.
How does this mortgage interest calculator work?
This calculator estimates total interest paid, not just monthly payments. It shows how interest accumulates over time and helps homeowners understand the real cost of keeping their current mortgage.
Is refinancing a mortgage worth it in 2025?
Refinancing can be worth it if you can secure a lower interest rate, shorten your loan term, or reduce total interest paid. Many homeowners refinance not to lower monthly payments, but to save long-term interest.
How much interest can I save by refinancing?
Savings vary, but even a 1% rate reduction can save $30,000 to $100,000+ over the life of a mortgage, depending on loan balance and remaining term.
Does refinancing always lower monthly payments?
Not necessarily. Some homeowners refinance to pay off their loan faster, which can increase monthly payments but dramatically reduce total interest paid.
What credit score is needed to refinance a mortgage?
Most lenders require a minimum credit score between 620 and 680, though better rates are typically offered to borrowers with 700+ scores.
How much does a mortgage refinance really cost?
Refinance closing costs usually range from 2% to 5% of the loan amount. However, these costs are often offset by long-term interest savings.
How long does it take to break even on a refinance?
The break-even point depends on closing costs and monthly savings. Many homeowners break even within 24 to 36 months, while others benefit sooner if rates drop significantly.
Refinance vs keeping your current mortgage — which saves more?
Keeping your current mortgage may feel simpler, but refinancing can significantly reduce total interest paid. The best option depends on your rate, remaining balance, and long-term plans.
Refinance vs HELOC: what’s the difference?
A refinance replaces your existing loan with a new one, often at a lower rate. A HELOC is a separate loan based on home equity, usually with variable rates and different risks.
When is refinancing a bad idea?
Refinancing may not be ideal if you plan to sell soon, have high closing costs, or cannot secure a meaningfully lower interest rate.
Can I refinance with my current lender?
Yes. Many homeowners refinance with the same lender, though comparing offers from multiple lenders often results in better rates and terms.
Does refinancing reset the loan term?
In most cases, yes. Refinancing often resets the mortgage to a new 15- or 30-year term, unless you choose a shorter option.
Why do banks rarely explain total interest clearly?
Monthly payments are easier to market. Total interest paid over decades is harder to explain — and far more profitable for lenders.
Should I compare refinance options before deciding?
Absolutely. Comparing refinance rates, terms, and costs is essential to understand how much interest you could realistically save.