HELOC Payment & Borrowing Power Calculator (2026)
Calculate your maximum Home Equity Line of Credit (HELOC), 10-year interest-only draw payments, 20-year principal + interest repayment shock, and available equity.
United States Calculator
Adjust Your Inputs
Move the sliders or type exact numbers. Results update instantly.
Instant Estimate
Your Results
Draw Phase Monthly Payment (Interest-Only, 10 Yrs)
$425
Based on your selected heloc calculator assumptions. Try different sliders to compare scenarios.
Repayment Phase Payment (Principal + Interest, 20 Yrs)
$521
Maximum Available HELOC Credit Line
$150,000
Remaining Untapped Home Equity
$190,000
Estimated Total Interest (Over Full Term)
$115,967
These calculations are financial projections and planning estimates, not tax, legal or licensed financial advice. 2026 IRS thresholds and mortgage lender rates vary by location.
How to Use the HELOC Calculator
Enter property market value & 1st mortgage
Input your home current market value and remaining balance on your primary mortgage.
Choose lender CLTV limit
Select 80%, 85%, or 90% Combined Loan-to-Value based on your lender guidelines.
Enter desired draw amount & interest rate
Specify how much equity you plan to tap and your variable interest rate (Prime Rate + lender margin).
Review draw payment vs repayment payment shock
See your 10-year interest-only draw payment alongside your 20-year principal + interest repayment shock.
Formula & Calculation Methodology
Max HELOC = (Home Value × Max LTV%) - First Mortgage | Draw Payment = Drawn × Rate / 12 | Repay Payment = Amortized(Drawn, Rate, 240)This calculator uses standard United States financial formulas, IRS thresholds, and amortization schedules. All results compute instantly in your browser with zero data stored or transmitted.
Calculation Examples & Scenarios
$500,000 Home with $250k Mortgage (80% CLTV Limit)
$500,000 value, $250,000 1st mortgage, 80% CLTV ($400,000 total allowable debt), $60,000 HELOC draw at 8.5% rate.
$700,000 Home Tapping $120,000 at 9.0%
$120,000 drawn for major home addition.
Key Benefits
- Accurately calculates available equity under 80%, 85%, and 90% Combined Loan-to-Value (CLTV) caps
- Directly visualizes the monthly payment jump between interest-only draw and amortized repayment
- Tracks remaining untapped equity to prevent overleveraging your primary residence
Common Use Cases
- Homeowners locked into 2%–3% primary mortgages tapping equity without refinancing their first loan
- Borrowers financing substantial home renovations that add appraisal value
- Consolidating high-interest credit card debt (22%–28% APR) into a single lower-rate line of credit
Understanding the HELOC 10-Year Draw vs. 20-Year Repayment Phase
A standard HELOC features a 10-year draw period during which borrowers can withdraw and repay funds flexibly, making interest-only monthly payments on the borrowed amount. Once the draw period closes, the line of credit freezes, and the loan converts into a 20-year fully amortized repayment phase where monthly payments include both principal and interest.
When is HELOC Interest Tax-Deductible?
Under current IRS regulations, HELOC interest is only tax-deductible if the loan proceeds are utilized exclusively to buy, build, or substantially improve the taxpayer home that secures the credit line. Interest on funds used for vacations, debt consolidation, or student tuition is strictly non-deductible.
Frequently Asked Questions
A Home Equity Line of Credit (HELOC) is a revolving line of credit secured by the equity in your home. Like a credit card, you have a borrowing limit and only pay interest on the money you actually draw. Most HELOCs have a 10-year draw period followed by a 20-year repayment period.
Payment shock occurs at the end of the 10-year draw period when you transition to the 20-year repayment phase. During the draw period, payments are typically interest-only. When the repayment period begins, you must pay both principal and interest, which can cause monthly payments to jump by 50% to 100% or more.
Most banks and mortgage lenders allow a maximum Combined Loan-to-Value (CLTV) of 80% to 85%. For example, on a $500,000 home with an 80% CLTV limit ($400,000) and an existing $250,000 mortgage balance, your maximum available HELOC credit line would be $150,000.
Under IRS rules (Tax Cuts and Jobs Act), HELOC interest is only tax-deductible if the borrowed funds are used to "buy, build, or substantially improve" the home that secures the loan. If you use HELOC funds to consolidate credit card debt or pay tuition, the interest is not deductible.
A HELOC is a revolving line of credit with a variable interest rate that fluctuates with the Prime Rate. A Home Equity Loan is a closed-end second mortgage that distributes funds in a single lump sum with a fixed interest rate and fixed monthly payments over the entire loan term.
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Related United States Guides
HELOC Payment Shock: How Monthly Payments Change from Draw to Repayment Phase
Understand the transition from 10-year interest-only HELOC draw payments to 20-year principal and interest repayment, and strategies to avoid severe monthly payment shock.
HELOC vs Home Equity Loan vs Cash-Out Refinance: Which is Best in 2026?
Compare the three primary ways to tap home equity: revolving variable-rate HELOCs, fixed second mortgages, and cash-out refinancing under current interest rates.