HELOC Payment / Payoff Calculator
Estimate your interest-only payment during a HELOC's draw period, and the amortizing payment once repayment begins.
How to Use
- While you're in the draw period, use "Draw period (interest-only)" — enter your currently drawn balance and rate to see your interest-only payment for that month.
- To estimate what you'll owe once repayment starts, use "Repayment period (amortizing)" — enter the balance you expect to owe when the draw period ends, an assumed rate, and the repayment term.
- HELOC rates are typically variable — re-run either calculation with a new rate any time your assumption changes, rather than expecting one result to hold for the whole draw or repayment period.
Formula
- Draw period payment
- interest_only_payment = drawn_balance × (rate ÷ 100 ÷ 12)
- Repayment period payment
- payment = balance × monthly_rate ÷ (1 − (1 + monthly_rate)^−months)
Worked Example
A $20,000 drawn balance at an 8.5% current rate.
- Monthly rate: 8.5 ÷ 100 ÷ 12 ≈ 0.007083
- Interest-only payment: $20,000 × 0.007083 ≈ $141.67
Result: Interest-only monthly payment during the draw period: $141.67
About This Tool
What this tool does
This calculator covers a HELOC's two distinct phases separately: the draw period, where you typically pay interest only on whatever you've currently borrowed, and the repayment period, where the remaining balance is paid off with a fixed, amortizing payment like a regular installment loan.
When to use it
Use the draw-period operation to check your current interest-only payment as your drawn balance changes, and the repayment-period operation to plan ahead for what your payment will look like once the draw period ends and principal payments begin.
What the result means
The draw-period payment covers only that month's interest — none of it reduces your balance, so your drawn amount stays exactly where it is unless you pay more voluntarily. The repayment-period payment includes principal and will fully retire the balance by the end of the term you enter.
Assumptions & limitations
HELOCs are conventionally variable-rate, and this tool never predicts or assumes a future rate on your behalf — every rate here is a plain, explicit assumption you enter, valid only for that specific calculation. If your real rate changes, re-run the calculator with the new rate rather than trusting an old result. The repayment-period figure assumes the rate you enter stays constant for the full repayment term, which a real variable-rate HELOC is not guaranteed to do. This is not a lending decision or an offer of credit.