HELOC Payment Calculator
HELOC interest-only and payoff monthly payments.
What it does
A HELOC splits into draws and payments: interest only while revolving, then payoff over a term. This page prices both monthly lines from balance and rate so draw decisions show their cost.
The default is $50,000 at 8.5%. Interest only is $354.17 per month while a 10 year payoff runs $619.93. The gap between them is principal progress versus treading water.
Variable rates move the answer. Prime plus margin resets change both lines at once, while floors stop falls and caps stop climbs. Stress the quote at the cap before counting on the minimum.
Use and taxes sit outside. IRS deductibility follows what the funds improve, and draw fees plus annual charges add to true cost beyond these two payments.
How to use
- Enter the drawn balance.
- Enter the current yearly rate.
- Read interest only first.
- Read the 10 year payoff next.
- Re run at the cap rate for stress.
Formula
- balance
- Drawn HELOC balance in dollars.
- rate
- Yearly variable rate in percent.
Draw periods are commonly interest only with principal due or amortized later; this page shows both shapes at the entered rate. Floors, caps, margins, and fixed rate lock options come from the note and are not modeled.
Worked example
Example: $50,000 HELOC
$50,000 balance at 8.5% variable rate.
- Interest only: 50,000 x 8.5 / 100 / 12 = $354.17.
- Monthly rate: 8.5 / 100 / 12 = 0.007083.
- Factor: 1 - 1.007083^-120 = 0.5713.
- Payoff: 50,000 x 0.007083 / 0.5713 = $619.93.
- Tool shows $354.17 interest only and $619.93 payoff.
Reference table
| Rate | Interest/mo | 10-yr/mo |
|---|---|---|
| 6% | $250.00 | $555.10 |
| 7% | $291.67 | $580.54 |
| 8.5% | $354.17 | $619.93 |
| 10% | $416.67 | $660.75 |
| 12% | $500.00 | $717.35 |
Limits
- Two shapes only. Fixed locks differ.
- No floors, caps, or margins modeled.
- Ignores fees and draw limits.
- Tax use rules excluded.
Common mistakes
- Budgeting interest only past the draw period.
- Reading variable as fixed.
- Forgetting floors under falls.
- Mixing APR with margin.
- Ignoring fees in true cost.
Try it yourself
Quick checks. Answers sit tucked under each question.
$30,000 at 7%?
Interest $175.00, payoff $348.33.
$100,000 at 10%, interest only?
Interest $708.33 (100,000 x 10 / 100 / 12).
Questions
Interest-only payment?
Balance times rate over 12. Here $354.17.
Full payoff payment?
Amortized over 10 years at the same rate. Here $619.93.
Variable rates?
Yes. Re run with the new rate when it resets.
Fees included?
No. Draw fees, annual fees, and floors sit outside payment math.
Tax deductible?
No. Tax deductibility follows IRS rules for use of funds.
Which payment?
Interest only leaves the balance standing; payoff clears it in 10 years.