HELOC Borrowing Power Calculator — How Much Can You Borrow?

How Much Can You Borrow?

Home Value

Use a recent appraisal or estimate

Remaining Mortgage Balance

What you still owe on your primary mortgage

Other Liens / 2nd Mortgages

Existing HELOC or second mortgage balance, if any

Lender LTV Limit

Most lenders allow 80–90% CLTV

Lenders calculate your Combined Loan-to-Value (CLTV) — all debt secured against your home, divided by its value. Most allow you to borrow up to 80–90% CLTV, though this varies by lender, credit score, and loan type.

Maximum HELOC Credit Line

Available equity you could borrow

Current CLTV

Combined loan-to-value today

Equity Breakdown

Item	Amount
Home Value	$0
Total Existing Debt (mortgage + liens)	$0
Maximum Allowed Debt at LTV Limit	$0
Available HELOC Credit Line	$0

What this means

Based on your numbers, your home has enough equity to support a HELOC at your lender's LTV limit.

How Lenders Calculate Your Borrowing Power

Your HELOC borrowing power isn't based on your home's value alone — it's based on your available equity after subtracting everything you already owe against the property. Lenders express this as a ratio called Combined Loan-to-Value, or CLTV.

The Formula

Lenders typically use this calculation:

(Home Value × Maximum LTV%) − Existing Mortgage Balance − Other Liens = Available HELOC Credit Line

For example, on a $450,000 home with an 85% LTV limit and a $220,000 mortgage balance, the maximum combined debt allowed is $382,500. Subtracting the existing mortgage leaves $162,500 in potential HELOC credit.

Why Lenders Set an LTV Limit

The LTV limit protects the lender if home values fall. By capping combined debt below 100% of the home's value, lenders maintain a buffer of equity that reduces their risk if you're unable to make payments. Limits commonly range from 80% to 90%, depending on the lender, your credit score, and whether the loan is for a primary residence or investment property.

Important

This calculator estimates your maximum theoretical credit line. Actual approval also depends on your credit score, debt-to-income ratio, income verification, and the specific lender's underwriting criteria. Always confirm your exact figure directly with a lender.

What Counts as "Other Liens"?

If you already have a second mortgage, an existing HELOC, or any other loan secured against your home, lenders include this in the CLTV calculation. This reduces your available borrowing power even if your primary mortgage balance is low.

Next Steps

Once you know your maximum credit line, the next question is usually what your monthly payments would look like. Try our HELOC Payment Calculator to estimate payments on the amount you're considering borrowing.

Borrowing Power FAQs

Most lenders allow a combined loan-to-value (CLTV) of 80% to 90%. Credit unions and some online lenders occasionally go higher, while stricter lenders may cap at 75–80%, particularly for investment properties or borrowers with lower credit scores.

Yes. While the LTV limit sets a ceiling, lenders also factor in your credit score and debt-to-income ratio when deciding your actual approved credit line. A lower credit score may mean a lower LTV limit or a smaller approved amount, even if your equity supports more.

Almost never. Lenders maintain an equity buffer to protect against falling home values, so very few will lend up to 100% CLTV. The vast majority cap combined debt well below the home's full value.