# What will my HELOC payment be?

Computes the home equity line of credit a combined loan-to-value limit allows, the interest-only payment in the draw period, and the payment and total interest in the repayment period.

- Page: https://www.acalculator.org/finance/heloc-calculator
- JSON spec: https://www.acalculator.org/finance/heloc-calculator.json
- Version: bdf4a2fe70b4

## Default answer

Example with the default inputs (Home value $450,000.00, Mortgage balance $250,000.00, Lender’s limit (combined loan-to-value) 85%, Amount you draw $50,000.00, Interest rate 8.5%, Draw period (years) 10, Repayment period (years) 20, Draw date September 30, 2026) on the example date Wednesday, September 30, 2026: Drawing $50,000.00 at 8.5% costs $354.17 a month in the draw period and $433.91 a month in the repayment period.

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| value | Home value | What your home is worth today, for example from an appraisal. |
| owed | Mortgage balance | What you still owe on your mortgage and any other loans secured by the home. |
| cltv | Lender’s limit (combined loan-to-value) | The most all loans on the home may add up to, as a percent of its value. |
| draw | Amount you draw | How much of the credit line you borrow, taken at the start of the draw period. |
| rate | Interest rate | The yearly rate on the line, taken as fixed. The monthly rate is this ÷ 12. |
| drawYears | Draw period (years) | The years you can borrow and pay only the interest. |
| repayYears | Repayment period (years) | The years you repay the balance with principal and interest. |
| start | Draw date | The day you draw the money. The first payment is one month later. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| drawPayment | Payment in the draw period | The interest-only monthly payment in the draw period: the amount drawn × the rate ÷ 12. |
| repayPayment | Payment in the repayment period | The level monthly payment that repays the amount drawn over the repayment period. |
| jump | Payment rise | How much the payment goes up when the repayment period starts. |
| line | Credit line | The most you can borrow: the home value × the limit − what you owe. |
| unused | Credit left unused | The credit line minus the amount you draw. |
| interest | Total interest | All the interest over the draw and repayment periods. |
| total | Total paid | The amount drawn plus all the interest. |
| combined | Combined loan-to-value | What you owe plus the amount drawn, as a percent of the home value. |
| repayStart | First repayment payment | The month of the first principal and interest payment, when a draw date is given. |

## Method

credit line = V × limit − owed; draw-period payment = D × r; repayment payment = D × r ÷ (1 − (1 + r)^−R), with D the amount drawn, r the rate ÷ 12, and R the repayment months.

## Assumptions

- You draw the whole amount at the start and borrow nothing more.
- The rate stays fixed; most HELOCs have a variable rate, so real payments change with it.
- In the draw period you pay only the interest; the repayment period repays the balance in level monthly payments.
- Interest is charged monthly at the yearly rate ÷ 12, and nothing is rounded between months.
- Fees such as appraisal, annual, or closing fees are not included.

## Worked examples

1. value = $450,000.00, owed = $250,000.00, cltv = 85%, draw = $50,000.00, rate = 8.5%, drawYears = 10, repayYears = 20 gives line = $132,500.00, drawPayment = $354.17, repayPayment = $433.91, interest = $96,638.79, combined = 66.666667%. Source: CFPB, What you should know about home equity lines of credit: interest-only payments in the draw period, then repayment.
2. value = $300,000.00, owed = $150,000.00, cltv = 80%, draw = $90,000.00, rate = 9%, drawYears = 5, repayYears = 15, start = 2026-10-15 gives line = $90,000.00, unused = $0.00, drawPayment = $675.00, repayPayment = $912.84, repayStart = 2031-11-15.
3. value = $400,000.00, owed = $100,000.00, cltv = 85%, draw = $24,000.00, rate = 0%, drawYears = 1, repayYears = 10 gives drawPayment = $0.00, repayPayment = $200.00, interest = $0.00, line = $240,000.00.

## FAQ

### How is a HELOC payment calculated?

In the draw period most HELOCs ask only for the interest: the balance times the yearly rate ÷ 12. $50,000 at 8.5% is 50,000 × 0.085 ÷ 12 = $354.17 a month. In the repayment period the balance is repaid in level monthly payments of principal and interest, like a mortgage: $433.91 a month over 20 years.

### How much can I borrow with a HELOC?

Lenders usually cap all loans on the home at a percent of its value, often 80% to 85%. The line is the home value times that limit minus what you owe. A $450,000 home with $250,000 owed and an 85% limit gives 450,000 × 0.85 − 250,000 = $132,500.

### What is the difference between the draw period and the repayment period?

In the draw period, often 10 years, you can borrow from the line and usually pay only interest. In the repayment period, often 20 years, you can no longer borrow and you repay the balance with interest. Some plans instead end with a balloon payment of the whole balance.

### Why can my HELOC payment change?

Most HELOCs have a variable rate tied to an index such as the prime rate, so the payment moves when the rate moves. The payment also rises when the repayment period starts. This page keeps the rate fixed, so try a higher rate to see the risk.

### Is a HELOC or a home equity loan better?

A home equity loan gives you one lump sum at a fixed rate and a fixed payment. A HELOC lets you borrow only what you need, when you need it, usually at a variable rate. Pick the loan that matches how you will use the money.

### What happens if I cannot repay a HELOC?

A HELOC is secured by your home, so the lender can foreclose if you do not repay. Borrow only what you can repay, including after the payment rises.

## Sources

- Consumer Financial Protection Bureau, What you should know about home equity lines of credit (draw period, repayment period, variable rates, balloon payments). https://files.consumerfinance.gov/f/documents/cfpb_heloc-brochure_print.pdf
- Federal Trade Commission, Home Equity Loans and Home Equity Lines of Credit. https://consumer.ftc.gov/articles/home-equity-loans-and-home-equity-lines-credit
- Amortized loan payment (annuity) formula: S. A. Broverman, Mathematics of Investment and Credit, chapter 3.