HELOCs typically have a 10-year draw period followed by 20 years of repayment, with a variable rate tied to the prime rate. Payment shock when the draw period ends is the biggest risk – plan for the higher payment.
How to use the HELOC Calculator – Home Equity Line of Credit
- Home value
- Mortgage balance
- Maximum combined LTV
- Amount drawn
- HELOC interest rate
- Draw period
- Repayment period
- Closing costs and fees
Results update as you type, and every field accepts the units shown in its menu.
How it works
Enter the home value, mortgage balance, lender’s CLTV limit, the amount you draw, the rate, the draw and repayment periods and fees.
Tips
- Compare loans by APR and total cost, not just the monthly payment.
- Extra payments go straight to principal and can save a lot of interest.
- Pay off the highest-rate debt first if you want to save the most money.
- Check for prepayment penalties before paying a loan off early.
Common mistakes to avoid
- Stretching a loan term to lower the payment without seeing the extra interest.
- Paying only the minimum on credit cards.
- Forgetting fees that are rolled into the loan.
Inputs explained
| Field | What to enter |
|---|---|
| Home value | Amount in your currency |
| Mortgage balance | Amount in your currency |
| Maximum combined LTV | In % |
| Amount drawn | Amount in your currency |
| HELOC interest rate | In % |
| Draw period | In years |
| Repayment period | In years |
| Closing costs and fees | Amount in your currency |
What each result means
- Maximum credit line = max([Home value]×[Maximum combined LTV]÷100 – [Mortgage balance], 0)
- Interest-only payment during the draw period = [Amount drawn]×[HELOC interest rate]÷1200
- Payment during repayment = pmt([HELOC interest rate]÷1200, [Repayment period]×12, [Amount drawn])
- Interest during the draw period = [Interest-only payment during the draw period]×[Draw period]×12
- Interest during repayment = [Payment during repayment]×[Repayment period]×12 – [Amount drawn]
- Total cost (interest + fees) = [Interest during the draw period] + [Interest during repayment] + [Closing costs and fees]
- Combined LTV with the draw = ([Mortgage balance] + [Amount drawn])÷[Home value]×100
Example values
How the main result changes when Home value changes and everything else stays at the example values above:
| Home value | Interest-only payment during the draw period |
|---|---|
| 250,000 | 387.5 |
| 375,000 | 387.5 |
| 500,000 | 387.5 |
| 625,000 | 387.5 |
| 750,000 | 387.5 |
| 1,000,000 | 387.5 |
Formula
Maximum line = home value × CLTV limit − mortgage balanceDraw-period payment (interest only) = balance × rate ÷ 12Repayment payment = pmt(rate ÷ 12, repayment months, balance)Worked example
Inputs — Home value: $500,000; Mortgage balance: $280,000; Maximum combined LTV: 85 %; Amount drawn: $60,000; HELOC interest rate: 7.75 %; Draw period: 10 years; Repayment period: 20 years; Closing costs and fees: $500.
Results — Maximum credit line = $145,000.00; Interest-only payment during the draw period = $387.50; Payment during repayment = $492.57; Interest during the draw period = $46,500.00; Interest during repayment = $58,216.59; Total cost (interest + fees) = $105,216.59; Combined LTV with the draw = 68 %.
Frequently asked questions
How much can I borrow with a HELOC?
Usually up to 80–90% of your home's value minus your mortgage.
Are HELOC rates variable?
Most are, based on the prime rate plus a margin.
Is HELOC interest tax-deductible?
Only if used to buy, build or substantially improve the home.
What formula does the HELOC Calculator – Home Equity Line of Credit use?
Maximum line = home value × CLTV limit − mortgage balance.