Broker DaveMortgage payoff comparison
The money you have left each month is what pays a house off. This runs that same monthly total through the mortgage you already have, a new fixed loan, and a line of credit that replaces your mortgage, then shows when each one is paid off and what it costs in total.
Your mortgage today
The principal balance on your statement.
Episode 1 uses a recent Freddie Mac 30-year average, not a quote or an offer. Put the rate from your own statement here.
30 yrs left · principal & interest $2,018.12 a month
Your monthly cash
Per month, after taxes. It stays out of the emailed summary.
Monthly total toward the house: $4,500 = $2,018 required + $2,482 extra principal
A new fixed loan (an example)
Use the rate from a real quote, or load an Episode 1 example.
15 yrs; 180 is a 15-year. Enter a rate to see the required payment.
An example, financed into the new loan: lender fees, title, appraisal.
The line of credit
An assumption you enter, not a quote. Use the rate from a real disclosure.
A line can charge an upfront fee. Use the one from the lender's disclosure.
Title, valuation, recording. Added to the starting balance with the fee.
Most lines are variable: the rate can rise, up to the maximum in the agreement.
Added to the line's rate for the rest of the payoff.
The rise starts after 1 yr.
85 months to pay off $300,000 at 7.11%. Every row below is measured against this. Enter a rate for a new loan or a line, or load an Episode 1 example, to compare.
Your options, side by side
Every row except “on schedule” sends the same $4,500 a month to the house, and every difference is measured against keeping your mortgage and paying that same total.
| vs. keeping your mortgage | Payoff | Total cost | Interest | Upfront fees & costs | Monthly cash | |
|---|---|---|---|---|---|---|
| Keep your mortgage on scheduleuses less cash each month | less cash | 30.0 yrs360 mos | $426,523 | $426,523 | $0 | $2,018 |
| Keep your mortgage and pay the same totalthe baseline | Baseline | 7.1 yrs85 mos | $82,796 | $82,796 | $0 | $4,500 |
| Refinance into a new fixed loanclosing costs financed | Enter a new loan rate | |||||
| Replace it with a line paid like a loanfee and costs added to the balance | Enter a line rate | |||||
| Replace it with a line used as your checking accounta modeled cash-flow strategy; not every line works like a checking account | Enter a line rate | |||||
“Total cost” is interest plus every fee and closing cost, financed or not. The checking-account row is a modeled cash-flow strategy; not every line works like a checking account.
Illustration from your inputs: not a quote, an offer or an approval.
Break-even line rate
Enter a line rate, or load an Episode 1 example, to see the break-even line rate.
A line of credit is secured by your home
- It's secured by your home. Falling behind on the payments can put the house at risk.
- Most lines have variable rates that can rise, up to the maximum in the agreement.
- A lender can stop new draws or lower your limit in limited cases, including a significant drop in your home's value, missed payments, or a material change in your finances that leads the lender to believe you can't repay.
- You can redraw only during the draw period in the agreement.
Assumptions
- Principal and interest only. Taxes, insurance, HOA dues and escrow are left out of every row.
- Fixed loans charge interest monthly, at the rate divided by 12, and are paid at month end.
- The line charges interest daily, at the rate divided by 360 on 30-day months, added monthly. A lender that uses a 360-day year on actual calendar days charges a bit more.
- Paychecks arrive twice a month, and spending is spread evenly across the month.
- In the rows that keep a mortgage, money waiting in checking between paydays earns nothing. If your account pays interest, the checking-account row's edge is smaller.
- Fees and closing costs are added to the starting balance.
- Rates stay the same for the whole payoff unless the stress test is on.
- Every row except “on schedule” uses the same monthly cash.
- Payoff is measured the same way for every row: at month end.
- The line rate is an assumption you enter, not a quote.
- There's no eligibility check: this doesn't look at credit, income, the home's value or lender rules.
Email me this analysis
Three ways to send the same money to the house
Keep it and prepay
No application, no closing costs, no new loan. Send more than the required payment and the extra goes straight to principal. On a fixed-rate mortgage the required principal-and-interest payment never changes, so in a tight month you can drop back to it.
Refinance into a new fixed loan
A new rate and term, closing costs to get them, and a bigger required payment if the term is shorter. It wins when the rate drop is big enough to pay for the costs. Check its payment against what you can send every month.
Replace it with a line
A home equity line of credit (a HELOC) in first position, so it replaces your mortgage. Paid like a loan, it's the same arithmetic as a mortgage at the line's rate. Used as your checking account, paychecks land on it and bills come out of it, so the balance dips between paydays. That edge is small, and a higher rate or an upfront fee wipes it out.
Before you replace a mortgage with a line
- It's still debt secured by your home. A line of credit isn't free money or a shortcut around repaying. Fall behind and the house is at risk.
- Compare total cost, not the rate. An upfront fee of a few percent can outweigh years of daily-interest edge. That's why every row above counts interest, fees and closing costs together.
- A low fixed rate is worth keeping. If your mortgage rate sits well below what a line would charge, the comparison says keep it. Try the “2.875% mortgage” example to see how far apart they land.
- Access has limits. A lender can stop new draws or lower your limit in limited cases, including a significant drop in your home's value, missed payments, or a material change in your finances that leads the lender to believe you can't repay. You can redraw only during the draw period in the agreement.
- This is principal and interest only. Taxes, insurance and HOA dues are left out of every row. A line may have no escrow account, so you'd pay taxes and insurance yourself.
This calculator is educational. It is not a loan offer, a rate quote, an approval or a commitment to lend. Rates, fees and terms vary by lender, credit, property and state. Every figure is an estimate, and most lines of credit have variable rates. Not tax or legal advice. David Lurvey, NMLS 410420. Equal Housing Opportunity.
Know the extra, not the total?
This tool asks for the total you send each month. The extra payment calculator asks for the extra on top of your payment, and shows both schedules side by side.
Extra payment calculatorHave a payoff date in mind?
Tell the early payoff calculator when you want to be done. It solves for the payment, then weighs it against refinancing into a 15-year.
Early payoff calculatorWant a lower payment instead?
A line can give cash back during its draw period, unless the lender freezes or lowers it. A recast gives you a lower required payment: a lump sum to principal, same rate, same payoff date.
Recast calculatorThe Mortgage Payoff Experiment
The series behind this calculator. We test mortgage strategies, run the numbers, and show homeowners what actually works, including the cases where the answer is “keep the mortgage you have.”
About the seriesFor a line behind your first mortgage
Keeping your first mortgage and adding a line or a home equity loan behind it is a different setup from the one above. That calculator compares those two, including the payment after the draw period ends.
Line vs. home equity loanSources. Freddie Mac, Primary Mortgage Market Survey (freddiemac.com/pmms), November 12, 2026: 30-year fixed 7.11%, 15-year fixed 6.45%, the rates in Episode 1's examples. The survey averages purchase loans with 20% down and strong credit. The line rate in the examples is an assumption, not a quote: Bankrate reports that lines of credit in first position typically carry variable rates and run about a point above a primary mortgage (bankrate.com, June 2, 2026). When a lender may stop draws or lower a line: Regulation Z, 12 CFR 1026.40(f)(3)(vi).