Combined loan-to-value is your total mortgage debt (existing mortgage plus the new HELOC) divided by your home's value. Lenders cap this to limit their risk, typically at 80-90%.

Do I have to draw the full available credit?

No. A HELOC is a revolving line of credit - you only pay interest on what you actually draw, similar to a credit card.

HELOC Calculator

Find out how much credit you could access with a home equity line of credit (HELOC), and estimate the interest-only payment on the amount you draw.

Home value

Current mortgage balance

Max combined loan-to-value

Lender's max CLTV, typically 80-90%

Interest rate (APR)

Amount you plan to draw

Available credit

$120,000.00

Interest-only monthly payment on draw$283.33

What Your Result Means

Available credit is how much a lender might let you borrow against your home's equity, based on their maximum combined loan-to-value (CLTV) ratio. The interest-only payment shows what you'd owe monthly during the draw period if you only pay interest on the amount you've actually drawn.

How It Is Calculated

Available Credit = (Home Value × Max CLTV%) - Current Mortgage Balance

Interest-Only Payment = Draw Amount × (Annual Rate / 12)

Worked Example

A $400,000 home with a $220,000 mortgage balance and an 85% max CLTV gives roughly $120,000 in available credit. Drawing $40,000 at 8.5% APR interest-only costs about $283/month.

Important Assumptions

Actual lender approval depends on credit score, income, and debt-to-income ratio, not just home equity.
Most HELOCs have a variable rate that can change over the draw period.

Frequently Asked Questions

What is CLTV?: Combined loan-to-value is your total mortgage debt (existing mortgage plus the new HELOC) divided by your home's value. Lenders cap this to limit their risk, typically at 80-90%.
Do I have to draw the full available credit?: No. A HELOC is a revolving line of credit - you only pay interest on what you actually draw, similar to a credit card.

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Methodology

This calculator uses standard combined loan-to-value formulas used by mortgage lenders. See our methodology page for details.

This calculator provides estimates for educational purposes only. Actual rates, taxes, insurance, fees, and lender terms may differ. It does not constitute financial advice - consult a qualified financial professional before making financial decisions.