HELOC vs. Cash-Out Refinance Blended Rate Simulator
Decide how to tap your home equity. Model the blended rate of keeping your low-rate first mortgage and adding a HELOC, versus refinancing your entire balance at current market rates.
Reviewed by Sarah Jenkins, Director of Underwriting — Last updated
First Mortgage & Equity Target
HELOC & Refinance Settings
Equity Access Comparison
| Payment / Cost Breakdown | HELOC Path (Blended) | Cash-Out Refi Path |
|---|---|---|
| First Mortgage Payment | $1,072 | $0 |
| Equity Draw Payment (HELOC) | $751 | $0 |
| New Refinance Payment | $0 | $2,150 |
| Total Monthly Outlay | $1,823 | $2,150 |
Verdict: Keeping your 3.125% rate and adding a HELOC at 8.75% yields a blended rate of 4.42%, saving you significant money over refinancing the entire balance.
HELOC vs Cash-Out Refinancing Handbook
Evaluating home equity borrowing strategies
What this engine does
This simulator evaluates the math behind keeping your primary mortgage intact and adding a HELOC, versus refinancing your entire mortgage balance to pull cash out.
When to deploy this tool
Use this tool when you need to access equity for home renovations, consolidating high-interest debt, or other funding needs, and want to avoid losing a low primary rate.
How Calculations Work
We calculate the combined blended rate of your first mortgage and equity draw, then compare it to the single rate and increased loan size of a cash-out refinance that includes closing costs.
Common Strategic Pitfalls
A common mistake is refinancing a large, low-rate first mortgage to tap a relatively small amount of equity. This moves your entire balance to a higher rate. Another mistake is ignoring HELOC rate volatility: most HELOCs have variable rates, meaning your costs could escalate if market rates rise.
Sources & Assumptions
Calculations are based on industry-standard financial models. To review the mathematical formulas and verification reports in detail, visit our dedicated Financial Methodology page.
Pre-populated data reflects estimated national averages sourced from county tax agencies and regional insurance reports. Homeowners can customize these percentages inside advanced settings cards.
PMI is modeled at 0.75% of the initial loan principal annually for LTV ratios exceeding 80%, automatically terminating in calculations when the outstanding loan balance drops to or below 80% of the initial purchase price.
Frequently Asked Questions
What is a blended mortgage rate?
A blended mortgage rate is the weighted average interest rate of multiple loans on a single property (typically your first mortgage plus a second mortgage or HELOC). It represents your true overall cost of borrowing across all balances.
When should I choose a HELOC over a cash-out refinance?
A HELOC is generally better if you have a very low interest rate on your first mortgage (e.g., under 4%) and only need to borrow a moderate amount of equity. A cash-out refinance makes sense if current market rates are lower than your first mortgage rate, or if you need to borrow a large sum for a long period.
What are the closing costs for a cash-out refinance?
Cash-out refinance closing costs typically range between 2% and 5% of the new total loan amount. These fees cover appraisals, title insurance, loan origination, and underwriting.
Are HELOC interest rates fixed or adjustable?
Most HELOCs have variable interest rates tied to the prime rate, meaning your monthly payments can fluctuate. However, some lenders offer hybrid HELOCs that allow you to lock in a fixed rate on specific drawn balances.
How much equity can I withdraw with a HELOC or cash-out refinance?
Lenders typically limit your total loan-to-value (LTV) ratio to 80% or 85% of your home's appraised value. This means you must retain at least 15% to 20% equity in the property after borrowing.
Is the interest on a HELOC tax-deductible?
Under IRS rules, HELOC interest is only tax-deductible if the funds are used to buy, build, or substantially improve the home that secures the loan. Interest is not deductible if used for personal expenses like credit card debt or vacations.
What credit score is needed for a HELOC?
Lenders generally require a credit score of at least 680 to qualify for a HELOC, though scores of 740 or higher are typically needed to secure the lowest rates and highest LTV ratios.
What DTI ratio is required for home equity borrowing?
Underwriters typically look for a back-end debt-to-income (DTI) ratio of 43% or lower, including your first mortgage, proposed HELOC payment, and all other monthly debts.
Can I get a HELOC if I have a second mortgage?
Usually no. Lenders rarely permit a third lien on a home. To get a HELOC, you would typically need to pay off the existing second mortgage or consolidate it into a new loan structure.
What happens if I default on a HELOC?
Because a HELOC is secured by your home, defaulting can result in foreclosure, just like a primary mortgage. The lender has the legal right to seize the property to recover their funds.
Financial Disclaimer
This calculator is intended for planning and educational purposes only. It relies on assumptions and information provided by you regarding your goals, expectations, and financial situation. Results should not be used as your sole source of information. Outputs are estimates only and do not constitute a loan offer, financial advice, legal advice, tax advice, or solicitation. Consult qualified professionals before making financial decisions.