HELOC Calculator
A HELOC leaves your first mortgage alone and adds a variable-rate line behind it. The risk is not the rate today — it is the payment step-up when the draw period ends.
Private by design. Your numbers stay on this device.
Educational estimates only. Not financial, tax, or lending advice.
How this works
A HELOC is a revolving line secured against your equity. During the draw period you can borrow and repay repeatedly, and many lenders require interest only — which retires none of the balance. When the draw period ends, the line converts to a repaying loan over a shorter term, and the payment jumps. Because the rate is variable, it can jump again. The rate stress field below exists for exactly that: set it to 2 or 4 points and see whether the payment still works.
Over your 7-year stay
Your first mortgage is untouched, so its rate is safe. What moves is the second payment — and it moves twice: when the draw period ends, and whenever the prime rate does.
- Keep current
- Monthly payment
- $2,767
- Net cost over your stay
- $465,286
- vs keeping your mortgage
- —
- Break-even
- —
- HELOC + mortgage
- Monthly payment
- $3,110
- Net cost over your stay
- $494,661
- vs keeping your mortgage
- -$29,375
- Break-even
- Never recovers
| Measure | Keep current | HELOC + mortgage |
|---|---|---|
| Interest rateThe rate on the new or largest loan in this scenario. | 6.875% | 8.25% |
| Starting loan balance | $320,000Low | $370,000 |
| Starting LTV (loan-to-value) | 71.1% | 82.2% |
| Principal & interest | $2,204Low | $2,548 |
| Extra principalVoluntary principal on top of the scheduled payment. Part of what you pay each month, so it belongs in the all-in figure. | — | — |
| PMI | — | — |
| Property tax + insuranceIdentical across every scenario for the same home, but a real part of the monthly bill. | $563 | $563 |
| Monthly HOA dues | — | — |
| All-in monthly payment | $2,767Low | $3,111 |
| Total closing costs | NoneLow | $500 |
| Cash needed at closingClosing costs paid in cash, plus any lump sum you contribute. | $0Low | $500 |
| Cash received | None | $50,000 |
| Interest over 7 years | $145,286Low | $174,161 |
| Balance left after 7 yearsWhat you would still owe when you expect to sell or refinance again. | $280,138Low | $330,138 |
| Equity after 7 yearsHome value less the balance owed. Uses your assumed appreciation rate, which is 0% unless you change it — it is never used to remove mortgage insurance early. | $169,862Low | $119,862 |
| Invested balance after 7 yearsOnly the growth on this account is credited against net cost. The contributions are money you paid in, so counting the whole balance would count them twice. | — | — |
| Net cost over your planned stayCash closing costs + payments made + balance still owed − cash received. Excludes property tax, insurance and HOA, which are identical across scenarios. | $465,286Low | $494,661 |
| Savings vs keeping your mortgageThis is not the same as interest saved: it also counts the balance you still owe at the end of your stay and any cash you paid upfront. The row above reconciles the two. | BaselineLow | -$29,375 |
| Why that differs from interest saved | — | $28,875 more interest, less $50,000 of extra balance you start out owing, less $500 paid in cash at closing, plus $50,000 of cash you received — leaving you $29,375 worse off. |
| Break-even point“Ahead from month 1” means there was no upfront cost to recover. “Never recovers” means the costs are never paid back. | — | Never recovers |
| Simple paybackUpfront cash divided by the monthly payment saving. This is the number most people mean by break-even, and it flatters a refinance: it ignores the principal you stop paying down when the term restarts. The equity-adjusted figure above is the one to rank on. | — | No monthly saving |
| Time to payoff | 26 yearsLow | 30 years |
| Total interest, full term | $367,691Low | $461,190 |
| Lifetime cost (interest + costs) | $367,691Low | $461,690 |
How to read this: “Low” marks the lowest figure among the scenarios shown — it is not a recommendation. Net cost counts payments made plus the balance still owed at the end of your stay, minus cash received, which is what makes loans of different sizes and terms comparable.
Full amortization schedule
Every payment, month by month: how much goes to interest, how much retires principal, and what you still owe afterwards. The last money column is the all-in cost — principal, interest, any extra you send, mortgage insurance, property tax, homeowners insurance and HOA dues — which is the figure that actually leaves your account. Switch to the annual view for a year-by-year summary, or download the full schedule as a CSV that opens in Excel, Google Sheets and Numbers.
| Month | Payment date | Beginning balance | Payment | Principal | Interest | Extra principal | Ending balance | Cumulative interest | Mortgage insurance | Taxes & insurance | HOA | Total monthly cost | LTV |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Jan 01, 2026 | $320,000.00 | $2,204.15 | $370.82 | $1,833.33 | — | $319,629.18 | $1,833.33 | — | $562.50 | — | $2,766.65 | 79.9% |
| 2 | Feb 01, 2026 | $319,629.18 | $2,204.15 | $372.94 | $1,831.21 | — | $319,256.24 | $3,664.54 | — | $562.50 | — | $2,766.65 | 79.8% |
| 3 | Mar 01, 2026 | $319,256.24 | $2,204.15 | $375.08 | $1,829.07 | — | $318,881.16 | $5,493.61 | — | $562.50 | — | $2,766.65 | 79.7% |
| 4 | Apr 01, 2026 | $318,881.16 | $2,204.15 | $377.23 | $1,826.92 | — | $318,503.93 | $7,320.53 | — | $562.50 | — | $2,766.65 | 79.6% |
| 5 | May 01, 2026 | $318,503.93 | $2,204.15 | $379.39 | $1,824.76 | — | $318,124.54 | $9,145.29 | — | $562.50 | — | $2,766.65 | 79.5% |
| 6 | Jun 01, 2026 | $318,124.54 | $2,204.15 | $381.56 | $1,822.59 | — | $317,742.98 | $10,967.88 | — | $562.50 | — | $2,766.65 | 79.4% |
| 7 | Jul 01, 2026 | $317,742.98 | $2,204.15 | $383.75 | $1,820.40 | — | $317,359.23 | $12,788.28 | — | $562.50 | — | $2,766.65 | 79.3% |
| 8 | Aug 01, 2026 | $317,359.23 | $2,204.15 | $385.95 | $1,818.20 | — | $316,973.28 | $14,606.48 | — | $562.50 | — | $2,766.65 | 79.2% |
| 9 | Sep 01, 2026 | $316,973.28 | $2,204.15 | $388.16 | $1,815.99 | — | $316,585.12 | $16,422.47 | — | $562.50 | — | $2,766.65 | 79.2% |
| 10 | Oct 01, 2026 | $316,585.12 | $2,204.15 | $390.38 | $1,813.77 | — | $316,194.74 | $18,236.24 | — | $562.50 | — | $2,766.65 | 79.0% |
| 11 | Nov 01, 2026 | $316,194.74 | $2,204.15 | $392.62 | $1,811.53 | — | $315,802.12 | $20,047.77 | — | $562.50 | — | $2,766.65 | 79.0% |
| 12 | Dec 01, 2026 | $315,802.12 | $2,204.15 | $394.87 | $1,809.28 | — | $315,407.25 | $21,857.05 | — | $562.50 | — | $2,766.65 | 78.8% |
Showing 1–12 of 312 payments
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Each file is generated in your browser — nothing is uploaded. Scenarios with a second lien include a separate block for each loan.
Educational estimates only. Not financial, tax, or lending advice. Want every option side by side instead? Open the full comparison.
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