Consolidating debts or renovating? Use this mortgage calculator with heloc to see your combined monthly payment for both your primary mortgage and your Home Equity Line of Credit, along with your blended interest rate.
Mortgage + HELOC Calculator
Mortgage Calculator with HELOC Formula
To find the combined monthly obligation, we sum the standard mortgage payment and the HELOC payment. We also calculate the “Blended Rate” to show the effective interest rate across both loans:
Variables
- P1: Primary Mortgage Principal Balance.
- r1: Primary Mortgage Interest Rate.
- P2: HELOC Balance Used.
- r2: HELOC Interest Rate.
Related Calculators
- HELOC Payment Calculator
- Blended Rate Calculator
- Cash-Out Refinance vs HELOC
- Debt Consolidation Calculator
What is Mortgage Calculator with HELOC?
A mortgage calculator with heloc is designed for homeowners managing two liens on their property. Whether you have taken out a Home Equity Line of Credit (HELOC) for renovations, tuition, or debt consolidation, this tool helps you budget by aggregating both payments.
Furthermore, it calculates the Blended Rate. This is critical when deciding whether to refinance. If your blended rate (e.g., 4.8%) is lower than current market rates for a cash-out refinance (e.g., 6.5%), it usually makes sense to keep your current loans rather than refinancing into a new, higher-rate mortgage.
How to Calculate Mortgage with HELOC (Example)
Assume you have a first mortgage and a HELOC:
- Primary: $300,000 balance at 3.0% for 25 years remaining. Payment ≈ $1,422.
- HELOC: $50,000 balance used at 9.0% (Interest Only).
- HELOC Payment: $50,000 × 0.09 / 12 = $375/month.
- Total Payment: $1,422 + $375 = $1,797.
- Blended Rate: [($300k×3%) + ($50k×9%)] / $350k = 13,500 / 350,000 = 3.86%.
Frequently Asked Questions (FAQ)
During the “draw period” (usually the first 10 years), payments are typically Interest Only, meaning you pay only the interest accrued on the amount you borrowed. Some lenders may require a minimum payment like 1% or 1.5% of the balance.
The blended rate formula presented here is a weighted average of the interest rates based on the loan balances. It essentially tells you the effective rate you are paying on every dollar of debt secured by your home right now.
Once the draw period ends (often after 10 years), the loan enters the “repayment period.” You can no longer borrow money, and you must start paying back principal and interest, which will significantly increase your monthly payment.
Typically, no. HELOCs usually have variable interest rates tied to the Prime Rate. This means your payment can fluctuate when the Federal Reserve adjusts rates, unlike a standard fixed-rate primary mortgage.