$100,000 HELOC Payment: What It Costs at Every Rate (2026)
Roughly $708 a month interest-only at today's typical rate — and about $868 once repayment begins. The full table, plus what a six-figure line really costs over its life.
The Answer: $583–$833 Interest-Only, $775–$965 in Repayment
The payment on a $100,000 HELOC balance at a typical 8.5% rate is about $708/month interest-only during the draw period, rising to roughly $868/month when the balance amortizes over a 20-year repayment period. Every payment here scales exactly 2× the $50,000 figures — the formula is linear in the balance. Run your own numbers with the interest-only HELOC calculator.
| HELOC rate | Interest-only payment (draw period) | 20-yr repayment payment | Interest over full 10-yr IO draw |
|---|---|---|---|
| 7.0% | $583.33 | $775.30 | $70,000 |
| 7.5% | $625.00 | $805.59 | $75,000 |
| 8.0% | $666.67 | $836.44 | $80,000 |
| 8.5% | $708.33 | $867.82 | $85,000 |
| 9.0% | $750.00 | $899.73 | $90,000 |
| 9.5% | $791.67 | $932.13 | $95,000 |
| 10.0% | $833.33 | $965.02 | $100,000 |
The scale is what makes a six-figure line dangerous on autopilot: interest-only for a full 10-year draw at 8.5% costs about $85,000 with zero principal reduction, and completing a 20-year repayment period afterwards brings total interest to roughly $108,000 — more than the amount borrowed. A 1-point prime increase moves this payment by about $83/month immediately.
See both phases of a $100,000 line — the interest-only payment now and the exact repayment-period jump — plus how voluntary principal changes the picture.
Calculate your HELOC paymentQualifying for (and Surviving) a $100,000 Line
Lenders typically cap combined loan-to-value (your mortgage plus the HELOC limit) at 80–85% of the home's value. Supporting a $100,000 line therefore generally requires at least $120,000–$125,000 of equity beyond your mortgage balance on an appraised-value basis, along with debt-to-income headroom for the fully amortizing payment — most underwriters qualify you at the repayment-phase number (or higher, stress-tested), not the interest-only teaser.
The gap between $708 interest-only and $868 in repayment is $160/month at a constant rate — and the rate isn't constant. If you can't comfortably carry the right-hand column of the table above, the responsible draw is smaller than the approved line. The Federal Reserve's HELOC booklet — the disclosure your lender is required to give you — walks through exactly this risk.
Paying voluntary principal during the draw period defuses most of it: $600/month of principal on top of interest clears $100,000 in about 11 years. Build that plan with the HELOC payoff calculator, or compare against a fixed-rate alternative with the home equity loan calculator.
- 1What is a home equity line of credit (HELOC)? — Consumer Financial Protection Bureau
- 2What You Should Know About Home Equity Lines of Credit — Federal Reserve Board
- 3Bank Prime Loan Rate (WPRIME) — Federal Reserve Bank of St. Louis (FRED)
Calculators for this guide
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We are a research-first finance team. We do not sell leads, we do not rank lenders, and we have no affiliates pulling our recommendations. Every guide is built by pairing primary sources — the IRS, CFPB, Federal Reserve, Freddie Mac, Statistics Canada, OSFI — with the same calculators you can run yourself.
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